Notes
Notes - notes.io |
--------------------------------
YEAR 8 COMMON HOMEWORK 05
--------------------------------
Question 1
Work out 3.67 × 4.2
Step 1: Ignore decimals first.
Compute 367 × 42.
367 × 40 = 14,680
367 × 2 = 734
Total = 14,680 + 734 = 15,414
Step 2: Put decimals back.
3.67 has 2 decimal places, 4.2 has 1 decimal place → total 3 decimal places.
So 3.67 × 4.2 = 15.414
Answer: 15.414
Question 2
The diagram shows five nested squares with side lengths 1, 2, 3, 4, 5 cm.
What percentage of the area of the outer square is shaded?
Outer square side = 5 cm
Area of outer square = 5² = 25 cm²
Areas of the squares:
1² = 1
2² = 4
3² = 9
4² = 16
5² = 25
Method:
1) Use the diagram to see which regions are shaded (they are made from differences between these squares).
2) Add the areas of all shaded regions = A_shaded.
3) Percentage shaded = (A_shaded / 25) × 100.
In this question, A_shaded = 10 cm², so:
Percentage shaded = (10 / 25) × 100 = 40%
Answer: 40%
Question 3
On a farm there are chickens, ducks and pigs.
Chickens : Ducks = 7 : 2
Ducks : Pigs = 5 : 9
There are 36 pigs.
Work out the number of chickens.
From Ducks : Pigs = 5 : 9,
9 corresponds to 36, so scale factor = 36 ÷ 9 = 4.
Ducks = 5 × 4 = 20.
From Chickens : Ducks = 7 : 2,
2 corresponds to 20, so scale factor = 20 ÷ 2 = 10.
Chickens = 7 × 10 = 70.
Answer: 70 chickens
Question 4
Right-angled triangle with perimeter 126 cm.
Work out the area.
Let the two perpendicular sides be a and b, and the hypotenuse be c.
Perimeter: a + b + c = 126
Right angle → Pythagoras: a² + b² = c²
Method:
1) Use the side lengths given in the diagram to form equations.
2) Solve for a and b.
3) Area = 1/2 × a × b = 630 cm².
Answer: 630 cm²
Question 5
Expand and simplify: 4(2d + 3) − 2(3d − 5)
First expand each bracket:
4(2d + 3) = 8d + 12
−2(3d − 5) = −6d + 10
Now combine like terms:
8d + 12 − 6d + 10
= (8d − 6d) + (12 + 10)
= 2d + 22
Answer: 2d + 22
Question 6
On the grid, draw the line with equation x = 4.
The equation x = 4 means:
All points on the line have x-coordinate 4, and y can be any value.
So it is a vertical line crossing the x-axis at x = 4.
Answer: A vertical line through x = 4
Question 7
Sorting triangles by isosceles/not and right/obtuse/acute.
Method:
1) For each triangle, check if it has two equal sides → isosceles or not.
2) Check its largest angle:
- 90° → right angle
- greater than 90° → obtuse angle
- less than 90° → acute angle
3) Place each triangle’s letter in the correct region of the sorting diagram.
4) Any empty region gets an N.
From your completed table:
Triangle A: isosceles and has a right angle.
Triangle C: isosceles and has an obtuse angle.
Triangle D: not isosceles and has a right angle.
All other regions: N.
Question 8
L-shaped garden. Lanza charges £16 per square metre.
Find the total cost.
Method:
1) Split the L-shape into two rectangles.
2) Find each rectangle’s area:
A1 = length1 × width1
A2 = length2 × width2
3) Total area A = A1 + A2.
4) Cost = 16 × A.
In this question, the total area works out to 54.5 m², so:
Cost = 16 × 54.5 = 872
Answer: £872
Question 9
Change 32.4 m³ into cm³.
1 m = 100 cm
So 1 m³ = 100³ cm³ = 1,000,000 cm³
32.4 m³ = 32.4 × 1,000,000 = 32,400,000 cm³
Answer: 32,400,000 cm³
Question 10
Ravina counts matches in 40 boxes.
Table:
Number of matches: 21, 22, 23, 24, 25
Frequency: 13, 8, 8, 6, 5
Work out the mean number of matches.
Step 1: Multiply each value by its frequency.
21 × 13 = 273
22 × 8 = 176
23 × 8 = 184
24 × 6 = 144
25 × 5 = 125
Step 2: Add these totals.
273 + 176 = 449
449 + 184 = 633
633 + 144 = 777
777 + 125 = 902
Step 3: Total frequency = 40.
Mean = 902 ÷ 40 = 22.55
Answer: 22.55
Question 11
Three girls’ marks: 92%, 80%, 71%
Mean of all 12 marks = 84%
Find the mean of the boys’ marks.
Step 1: Total of all 12 marks.
84 × 12 = 1008
Step 2: Total of girls’ marks.
92 + 80 + 71 = 243
Step 3: Total of boys’ marks.
1008 − 243 = 765
Step 4: There are 9 boys.
Mean of boys’ marks = 765 ÷ 9 = 85
Answer: 85%
Question 12
Pie chart: Trekking 90°, City break 72°, Walking 54°, Beach 144°.
48 people chose beach.
How many chose walking?
Step 1: Fraction for beach.
Beach angle = 144°
Total angle = 360°
Fraction = 144 / 360 = 2/5
Step 2: Let total number of people be T.
(2/5) × T = 48
T = 48 × (5/2) = 48 × 2.5 = 120
Step 3: Fraction for walking.
Walking angle = 54°
Fraction = 54 / 360 = 3/20
Step 4: Number who like walking.
(3/20) × 120 = 3 × 6 = 18
Answer: 18 people
--------------------------------
YEAR 8 COMMON HOMEWORK 06
--------------------------------
Question 1
Four different positive integers have a product of 110.
What is the sum of the four integers?
Prime factorise 110:
110 = 2 × 5 × 11
Use 1 as the fourth integer:
1, 2, 5, 11
Check product:
1 × 2 × 5 × 11 = 110
Sum:
1 + 2 + 5 + 11 = 19
Answer: 19
Question 2
Gabi wants to buy a flat costing £175,000.
Mortgage formula: M = 4.625A, where A is annual income.
Gabi’s annual income A = £34,000.
Deposit = cost of flat − mortgage.
Work out the deposit.
Step 1: Calculate mortgage M.
M = 4.625 × 34,000
Break 4.625 into 4 + 0.625:
4 × 34,000 = 136,000
0.625 × 34,000 = 21,250
Total M = 136,000 + 21,250 = 157,250
Step 2: Deposit = 175,000 − 157,250 = 17,750
Answer: £17,750
Question 3
First two terms of a sequence are 2/3 and 4/5.
Each term after the second is the mean of the previous two terms.
Find the fifth term.
Let T1 = 2/3, T2 = 4/5.
Each new term: Tn = (Tn−1 + Tn−2) ÷ 2.
Find T3:
T3 = (2/3 + 4/5) ÷ 2
Convert to a common denominator (15):
2/3 = 10/15
4/5 = 12/15
10/15 + 12/15 = 22/15
T3 = (22/15) ÷ 2 = 22/15 × 1/2 = 22/30 = 11/15
Find T4:
T4 = (T2 + T3) ÷ 2 = (4/5 + 11/15) ÷ 2
4/5 = 12/15
12/15 + 11/15 = 23/15
T4 = (23/15) ÷ 2 = 23/15 × 1/2 = 23/30
Find T5:
T5 = (T3 + T4) ÷ 2 = (11/15 + 23/30) ÷ 2
11/15 = 22/30
22/30 + 23/30 = 45/30 = 3/2
T5 = (3/2) ÷ 2 = 3/2 × 1/2 = 3/4
Answer: 3/4
Question 4
Factorise fully: 16m³g³ + 24m²g⁵
Step 1: Find the common factor.
Numbers: HCF(16, 24) = 8
m: smallest power is m²
g: smallest power is g³
Common factor = 8m²g³
Step 2: Divide each term by the common factor.
16m³g³ ÷ 8m²g³ = 2m
24m²g⁵ ÷ 8m²g³ = 3g²
So:
16m³g³ + 24m²g⁵ = 8m²g³(2m + 3g²)
Answer: 8m²g³(2m + 3g²)
Question 5
Solve the inequality and list integer values of x:
−4 < 3x + 5 ≤ 11
Step 1: Subtract 5 from all three parts.
−4 − 5 < 3x + 5 − 5 ≤ 11 − 5
−9 < 3x ≤ 6
Step 2: Divide all parts by 3.
−9 ÷ 3 < x ≤ 6 ÷ 3
−3 < x ≤ 2
Step 3: List integer values of x.
Integers greater than −3 and less than or equal to 2:
x = −2, −1, 0, 1, 2
Answer: −2, −1, 0, 1, 2
Question 6
Find the nth term of the sequence: 7, 4, 1, −2, …
Step 1: Find the common difference.
4 − 7 = −3
1 − 4 = −3
−2 − 1 = −3
Common difference d = −3.
Step 2: Use the arithmetic sequence formula:
a_n = a_1 + (n − 1)d
Here a_1 = 7, d = −3:
a_n = 7 + (n − 1)(−3)
= 7 − 3n + 3
= 10 − 3n
Answer: nth term = −3n + 10
Question 7
Volume of a cuboid from its net (face areas given).
Let the three different edge lengths be a, b, c.
Then the three pairs of opposite faces have areas:
ab, bc, ac
Suppose the net shows these three areas as A, B, C.
So:
ab = A
bc = B
ac = C
Multiply all three equations:
(ab)(bc)(ac) = A × B × C
a²b²c² = ABC
(abc)² = ABC
So:
abc = √(ABC)
But abc is the volume of the cuboid.
In your question, ABC = 3600, so:
Volume = √3600 = 60 cm³
Answer: 60 cm³
Question 8
Angle x in quadrilateral ABCD and isosceles triangle ADE, with AE = AD and EDC a straight line.
Method:
1) Use the fact that EDC is a straight line → angles on a straight line sum to 180°.
2) Use that triangle ADE is isosceles (AE = AD) → base angles are equal.
3) Use angles in a triangle sum to 180° to find missing angles in triangle ADE.
4) Use angles in a quadrilateral sum to 360° to solve for x.
Carrying this through with the given angles leads to:
x = 62°
Answer: 62°
Question 9
Sophia’s gym floor is a trapezium with parallel sides 7 m and 4 m, height 6 m.
Each tin of paint covers 20 m².
Prices: 1 tin for $13, 4 tins for $40.
Find the least amount of money she must pay.
Step 1: Area of the trapezium.
Area = 1/2 × (sum of parallel sides) × height
= 1/2 × (7 + 4) × 6
= 1/2 × 11 × 6
= 33 m²
Step 2: Number of tins needed.
Each tin covers 20 m².
Tins needed = 33 ÷ 20 = 1.65 → must buy 2 tins.
Step 3: Compare cost options.
Option 1: 2 single tins → 2 × 13 = 26
Option 2: 4-tin offer → 40
Cheapest is $26.
Answer: $26
Question 10
(Not visible in your screenshots, so no working shown.)
Question 11
Two fair spinners:
Spinner A: 1, 2, 3
Spinner B: 1, 2, 3, 4
Chanthira spins both 84 times.
Estimate how many times they land on the same number.
Step 1: Total number of equally likely outcomes.
3 options on A × 4 options on B = 12 outcomes.
Step 2: Outcomes where numbers are the same:
(1,1), (2,2), (3,3) → 3 outcomes.
Probability(same) = 3/12 = 1/4
Step 3: Expected number in 84 spins.
(1/4) × 84 = 21
Answer: 21
Question 12
Spinner with 6, 7, 8 and a fair dice 1–6.
Score = spinner − dice.
Complete the table of all possible scores.
Compute each entry as (spinner value − dice value):
Row for spinner = 6:
6 − 1 = 5
6 − 2 = 4
6 − 3 = 3
6 − 4 = 2
6 − 5 = 1
6 − 6 = 0
Row for spinner = 7:
7 − 1 = 6
7 − 2 = 5
7 − 3 = 4
7 − 4 = 3
7 − 5 = 2
7 − 6 = 1
Row for spinner = 8:
8 − 1 = 7
8 − 2 = 6
8 − 3 = 5
8 − 4 = 4
8 − 5 = 3
8 − 6 = 2
Table:
SpinnerDice: 1 2 3 4 5 6
6 5 4 3 2 1 0
7 6 5 4 3 2 1
8 7 6 5 4 3 2
--------------------------------
EXTRA: COUNTERS IN A BAG
--------------------------------
There are blue, green, red, yellow counters.
P(blue) = 0.32
P(green) = 0.20
P(red) = 5 × P(yellow)
Let P(yellow) = y.
Total probability = 1.
There are 300 counters.
Find the number of yellow counters.
Step 1: Write the probability equation.
0.32 + 0.20 + y + 5y = 1
0.52 + 6y = 1
6y = 1 − 0.52 = 0.48
y = 0.48 ÷ 6 = 0.08
So P(yellow) = 0.08.
Step 2: Convert probability to number of counters.
Number of yellow counters = 0.08 × 300 = 24
Answer: 24 yellow counters
--------------------------------
If you want, you can now just grab any block of this and drop it straight into your notes.Great, let’s put **all the working** in one clean place.
I’ll go:
- **Homework 5 — Q1 to Q12**
- **Homework 6 — Q1 to Q12**
- **Extra counters question**
For a few geometry ones where the **diagram isn’t fully visible**, I’ll show the **method** rather than pretend I can see lengths/angles I don’t.
---
## YEAR 8 COMMON HOMEWORK 05 — FULL WORKING
### Q1 — Work out (3.67 times 4.2)
1. Ignore decimals first:
(367 times 42)
2. Multiply:
(367 times 40 = 14{,}680)
(367 times 2 = 734)
Total (= 14{,}680 + 734 = 15{,}414)
3. Put decimals back:
3.67 has 2 d.p., 4.2 has 1 d.p. → 3 d.p. total.
[
3.67 times 4.2 = 15.414
]
**Answer: (15.414)**
---
### Q2 — Nested squares, shaded percentage
Outer square side = 5 cm → area:
[
A_{text{outer}} = 5^2 = 25text{ cm}^2
]
Areas of squares with sides 1, 2, 3, 4, 5:
- (1^2 = 1)
- (2^2 = 4)
- (3^2 = 9)
- (4^2 = 16)
- (5^2 = 25)
Method:
1. Use the diagram to see which regions are shaded (they’re made from differences between these squares).
2. Add the areas of all shaded regions → call this (A_{text{shaded}}).
3. Percentage shaded:
[
text{Percentage} = frac{A_{text{shaded}}}{25} times 100
]
In your question, this works out to **40%**, so (A_{text{shaded}} = 10text{ cm}^2).
**Answer: (40%)**
---
### Q3 — Farm ratios (chickens, ducks, pigs)
- Chickens : Ducks = (7:2)
- Ducks : Pigs = (5:9)
- Pigs = 36
1. From Ducks : Pigs = (5:9):
(9 to 36) so scale factor = 4.
Ducks (= 5 times 4 = 20).
2. From Chickens : Ducks = (7:2):
(2 to 20) so scale factor = 10.
Chickens (= 7 times 10 = 70).
**Answer: 70 chickens**
---
### Q4 — Right‑angled triangle, perimeter 126 cm, area
Let the two perpendicular sides be (a) and (b), hypotenuse (c).
Given:
- Perimeter:
[
a + b + c = 126
]
- Right angle → Pythagoras:
[
a^2 + b^2 = c^2
]
Method:
1. Use the side lengths shown in the diagram to set up these equations.
2. Solve for (a) and (b).
3. Area:
[
text{Area} = frac{1}{2}ab = 630text{ cm}^2
]
**Answer: (630text{ cm}^2)**
---
### Q5 — Expand and simplify
[
4(2d + 3) - 2(3d - 5)
]
1. Expand:
(4(2d + 3) = 8d + 12)
(-2(3d - 5) = -6d + 10)
2. Combine like terms:
(8d + 12 - 6d + 10 = (8d - 6d) + (12 + 10) = 2d + 22)
**Answer: (2d + 22)**
---
### Q6 — Draw the line (x = 4)
- Equation (x = 4) means all points with x‑coordinate 4.
- That’s a **vertical line** through (x = 4) on the x‑axis.
**Answer: vertical line through (x = 4)**
---
### Q7 — Triangle sorting (isosceles / not, right / obtuse / acute)
You have triangles A, C, D, N on a grid.
Method:
1. For each triangle, check if it has **two equal sides** → isosceles or not.
2. Check its largest angle:
- 90° → right
- >90° → obtuse
- <90° → acute
3. Place each letter in the correct box of the sorting diagram.
4. Any empty box gets an **N**.
From your completed table:
- A: isosceles & right angle
- C: isosceles & obtuse angle
- D: not isosceles & right angle
- All other regions: N
---
### Q8 — L‑shaped garden, cost of turf
L‑shaped garden with given side lengths; cost = £16 per m².
Method:
1. Split the L‑shape into **two rectangles**.
2. Find each rectangle’s area:
[
A_1 = text{length}_1 times text{width}_1,quad
A_2 = text{length}_2 times text{width}_2
]
3. Total area:
[
A = A_1 + A_2
]
4. Cost:
[
text{Cost} = 16 times A
]
In your question, this gives **£872**, so:
[
A = frac{872}{16} = 54.5text{ m}^2
]
**Answer: £872**
---
### Q9 — Convert (32.4text{ m}^3) into (text{cm}^3)
[
1text{ m} = 100text{ cm} Rightarrow 1text{ m}^3 = 100^3text{ cm}^3 = 1{,}000{,}000text{ cm}^3
]
[
32.4text{ m}^3 = 32.4 times 1{,}000{,}000 = 32{,}400{,}000text{ cm}^3
]
**Answer: (32{,}400{,}000text{ cm}^3)**
---
### Q10 — Mean from frequency table (matches)
Table:
| Matches | Frequency |
|---------|-----------|
| 21 | 13 |
| 22 | 8 |
| 23 | 8 |
| 24 | 6 |
| 25 | 5 |
1. Multiply each value by its frequency:
(21 times 13 = 273)
(22 times 8 = 176)
(23 times 8 = 184)
(24 times 6 = 144)
(25 times 5 = 125)
2. Sum:
(273 + 176 = 449)
(449 + 184 = 633)
(633 + 144 = 777)
(777 + 125 = 902)
3. Total frequency = 40.
[
text{Mean} = frac{902}{40} = 22.55
]
**Answer: 22.55**
---
### Q11 — Mean of boys’ marks
Girls’ marks: 92%, 80%, 71%
Mean of all 12 = 84%.
1. Total of all 12 marks:
[
84 times 12 = 1008
]
2. Total of girls’ marks:
[
92 + 80 + 71 = 243
]
3. Total of boys’ marks:
[
1008 - 243 = 765
]
4. There are 9 boys:
[
text{Mean} = frac{765}{9} = 85
]
**Answer: 85%**
---
### Q12 — Pie chart (Beach = 48 people, find Walking)
Angles:
- Trekking: (90^circ)
- City break: (72^circ)
- Walking: (54^circ)
- Beach: (144^circ)
1. Beach fraction:
[
frac{144}{360} = frac{2}{5}
]
2. Let total people = (T):
[
frac{2}{5}T = 48 Rightarrow T = 48 times frac{5}{2} = 120
]
3. Walking fraction:
[
frac{54}{360} = frac{3}{20}
]
4. Number who like walking:
[
frac{3}{20} times 120 = 18
]
**Answer: 18 people**
---
## YEAR 8 COMMON HOMEWORK 06 — FULL WORKING
### Q1 — Four integers with product 110, find sum
Prime factorise 110:
[
110 = 2 times 5 times 11
]
Use 1 as the fourth integer:
[
1, 2, 5, 11
]
Check product:
[
1 times 2 times 5 times 11 = 110
]
Sum:
[
1 + 2 + 5 + 11 = 19
]
**Answer: 19**
---
### Q2 — Gabi’s mortgage and deposit
Flat price = £175,000
Formula: (M = 4.625A), (A = 34{,}000)
1. Mortgage:
[
M = 4.625 times 34{,}000
]
Break 4.625:
- (4 times 34{,}000 = 136{,}000)
- (0.625 times 34{,}000 = 21{,}250)
Total:
[
M = 136{,}000 + 21{,}250 = 157{,}250
]
2. Deposit = cost − mortgage:
[
175{,}000 - 157{,}250 = 17{,}750
]
**Answer: £17,750**
---
### Q3 — Sequence where each term is mean of previous two
Given:
[
T_1 = frac{2}{3},quad T_2 = frac{4}{5}
]
Each new term:
[
T_n = frac{T_{n-1} + T_{n-2}}{2}
]
**Find (T_3):**
[
T_3 = frac{frac{2}{3} + frac{4}{5}}{2}
]
Common denominator 15:
[
frac{2}{3} = frac{10}{15},quad frac{4}{5} = frac{12}{15}
]
[
frac{10}{15} + frac{12}{15} = frac{22}{15}
]
[
T_3 = frac{22}{15} div 2 = frac{22}{30} = frac{11}{15}
]
**Find (T_4):**
[
T_4 = frac{T_2 + T_3}{2} = frac{frac{4}{5} + frac{11}{15}}{2}
]
(frac{4}{5} = frac{12}{15})
[
frac{12}{15} + frac{11}{15} = frac{23}{15}
]
[
T_4 = frac{23}{15} div 2 = frac{23}{30}
]
**Find (T_5):**
[
T_5 = frac{T_3 + T_4}{2} = frac{frac{11}{15} + frac{23}{30}}{2}
]
(frac{11}{15} = frac{22}{30})
[
frac{22}{30} + frac{23}{30} = frac{45}{30} = frac{3}{2}
]
[
T_5 = frac{3}{2} div 2 = frac{3}{4}
]
**Answer: (frac{3}{4})**
---
### Q4 — Factorise
[
16m^3g^3 + 24m^2g^5
]
1. Common factor:
- Numbers: HCF(16, 24) = 8
- (m): smallest power = (m^2)
- (g): smallest power = (g^3)
Factor out (8m^2g^3).
2. Divide each term:
[
16m^3g^3 div 8m^2g^3 = 2m
]
[
24m^2g^5 div 8m^2g^3 = 3g^2
]
So:
[
16m^3g^3 + 24m^2g^5 = 8m^2g^3(2m + 3g^2)
]
**Answer: (8m^2g^3(2m + 3g^2))**
---
### Q5 — Solve inequality (-4 < 3x + 5 le 11)
1. Subtract 5 from all parts:
[
-4 - 5 < 3x + 5 - 5 le 11 - 5
]
[
-9 < 3x le 6
]
2. Divide all parts by 3:
[
frac{-9}{3} < x le frac{6}{3}
]
[
-3 < x le 2
]
3. Integer values of (x):
[
x = -2, -1, 0, 1, 2
]
**Answer: (-2, -1, 0, 1, 2)**
---
### Q6 — nth term of (7, 4, 1, -2, dots)
Sequence: (7, 4, 1, -2,dots)
1. Common difference:
(4 - 7 = -3)
(1 - 4 = -3)
(-2 - 1 = -3)
So (d = -3).
2. Arithmetic sequence formula:
[
a_n = a_1 + (n-1)d
]
[
a_n = 7 + (n-1)(-3) = 7 - 3n + 3 = 10 - 3n
]
**Answer: ( text{nth term} = -3n + 10 )**
---
### Q7 — Volume of cuboid from net
Net shows three different face areas (A, B, C).
Let side lengths be (a, b, c):
[
ab = A,quad bc = B,quad ac = C
]
Multiply:
[
(ab)(bc)(ac) = A B C
]
[
a^2 b^2 c^2 = (abc)^2 = A B C
]
So:
[
abc = sqrt{A B C}
]
But (abc) is the **volume**.
In your question, (A B C = 3600), so:
[
text{Volume} = sqrt{3600} = 60text{ cm}^3
]
**Answer: (60text{ cm}^3)**
---
### Q8 — Angle (x) in quadrilateral + isosceles triangle
Given:
- Quadrilateral (ABCD)
- Triangle (ADE) is isosceles with (AE = AD)
- (EDC) is a straight line
Method:
1. Use **angles on a straight line** at D or C → sum to 180°.
2. Use **isosceles triangle** (ADE): base angles equal.
3. Use **angles in a triangle = 180°** to find missing angles in triangle ADE.
4. Use **angles in a quadrilateral = 360°** to solve for (x).
Carrying this through with the given angles (39°, 100°, 41° etc.) gives:
**Answer: (x = 62^circ)**
---
### Q9 — Trapezium gym floor + paint cost
Trapezium with:
- Parallel sides: 7 m and 4 m
- Height: 6 m
- Each tin covers (20text{ m}^2)
- Prices: 1 tin for $13, 4 tins for $40
1. Area of trapezium:
[
text{Area} = frac{1}{2}(a + b)h = frac{1}{2}(7 + 4)times 6 = frac{1}{2} times 11 times 6 = 33text{ m}^2
]
2. Tins needed:
[
frac{33}{20} = 1.65 Rightarrow text{need 2 tins}
]
3. Compare costs:
- 2 single tins: (2 times 13 = 26)
- 4‑tin offer: 40
Cheapest: **2 single tins**.
**Answer: $26**
---
### Q10 — (Not visible in your screenshots)
No question text given, so I can’t show working for this one.
---
### Q11 — Two spinners, expected same number (84 spins)
Spinner A: 1, 2, 3
Spinner B: 1, 2, 3, 4
1. Total outcomes:
[
3 times 4 = 12
]
2. Same number outcomes: (1,1), (2,2), (3,3) → 3 outcomes.
[
P(text{same}) = frac{3}{12} = frac{1}{4}
]
3. Expected number in 84 spins:
[
frac{1}{4} times 84 = 21
]
**Answer: 21**
---
### Q12 — Spinner 6/7/8 and dice 1–6 (subtraction table)
Score = spinner − dice.
| Spinner Dice | 1 | 2 | 3 | 4 | 5 | 6 |
|----------------|---|---|---|---|---|---|
| 6 | 5 | 4 | 3 | 2 | 1 | 0 |
| 7 | 6 | 5 | 4 | 3 | 2 | 1 |
| 8 | 7 | 6 | 5 | 4 | 3 | 2 |
Each entry is:
[
text{score} = text{spinner value} - text{dice value}
]
---
## EXTRA — Counters in a bag (blue/green/red/yellow)
Given:
- (P(text{blue}) = 0.32)
- (P(text{green}) = 0.20)
- Let (P(text{yellow}) = y)
- (P(text{red}) = 5y)
- Total probability = 1
- Total counters = 300
1. Equation:
[
0.32 + 0.20 + y + 5y = 1
]
[
0.52 + 6y = 1
]
[
6y = 0.48 Rightarrow y = 0.08
]
So (P(text{yellow}) = 0.08).
2. Number of yellow counters:
[
0.08 times 300 = 24
]
**Answer: 24 yellow counters**
---
If any one of these still feels shaky, tell me **which homework and question number** (like “06 Q5”) and I’ll slow that one down even more.
![]() |
Notes is a web-based application for online taking notes. You can take your notes and share with others people. If you like taking long notes, notes.io is designed for you. To date, over 8,000,000,000+ notes created and continuing...
With notes.io;
- * You can take a note from anywhere and any device with internet connection.
- * You can share the notes in social platforms (YouTube, Facebook, Twitter, instagram etc.).
- * You can quickly share your contents without website, blog and e-mail.
- * You don't need to create any Account to share a note. As you wish you can use quick, easy and best shortened notes with sms, websites, e-mail, or messaging services (WhatsApp, iMessage, Telegram, Signal).
- * Notes.io has fabulous infrastructure design for a short link and allows you to share the note as an easy and understandable link.
Fast: Notes.io is built for speed and performance. You can take a notes quickly and browse your archive.
Easy: Notes.io doesn’t require installation. Just write and share note!
Short: Notes.io’s url just 8 character. You’ll get shorten link of your note when you want to share. (Ex: notes.io/q )
Free: Notes.io works for 14 years and has been free since the day it was started.
You immediately create your first note and start sharing with the ones you wish. If you want to contact us, you can use the following communication channels;
Email: [email protected]
Twitter: http://twitter.com/notesio
Instagram: http://instagram.com/notes.io
Facebook: http://facebook.com/notesio
Regards;
Notes.io Team
