The Robert Smyth School
Mathematics Faculty
Topic 6
Ratio HW 1
Innovation & excellence
Topic 6 (Foundation) – Homework on Unitary Ratio
1.
The cost of 20 oranges is £9.
Find the cost of one orange.
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Answer ......................................................................
(3)
2.
A trader pays £14.80 for 20 melons.
How much does he pay for one melon?
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Answer .........................................................................
(Total 3 marks)
3.
Four melons cost £4.28
How much will five melons cost?
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Answer £ .....................................................................
(Total 3 marks)
4.
Fiona buys 4.4 kg of grapes for £5.94
How much does Alex pay for 3.6 kg of the same grapes?
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Answer £ .............………………………
(3)
The Robert Smyth School
1
The Robert Smyth School
Mathematics Faculty
Topic 6
Ratio HW 1
Innovation & excellence
5.
The cost of 30 bottles of water is £21.
(a)
What is the cost of 45 bottles of water?
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Answer ................................................
(3)
(b)
The cost of the bottles of water increases by 5%.
Increase £21 by 5%.
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Answer £ ................................................
(3)
6.
Carl buys 1.2 kg of potatoes and 0.4 kg of carrots. He pays 96p in total.
The potatoes cost 70p per kg.
What is the cost of 1 kg of carrots?
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Answer ........................................................................ pence
(4)
7.
Apples are sold in a farm shop at £1.76 per kilogram.
Calculate the price of 1 pound of apples.
Use the conversion 1 kilogram = 2.2 pounds
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Answer .........................................................................
(Total 3 marks)
The Robert Smyth School
2
The Robert Smyth School
Mathematics Faculty
Topic 6
Ratio HW 1
Innovation & excellence
Answers - Topic 6 (Foundation) – Homework on Ratio
1.
(£) 9 ÷ 20
M1
Or 900(p) ÷ 20
= 0.45A1
= 45
= £0.45(p)
B1
= 45p
Units mark
2.
[3]
Cost is £14.80  20
M1
= 74
A1
Cost is 74 pence
B1
Units mark
Accept £0.74
3.
4.
5.
1 melon costs
4.28
(= £1.07)
4
2.14
2
[3]
M1
5 melons cost 5 × £1.07
or £4.28 + £1.07
M1
= £5.35
A1
Cost of 1 kg is £ 5.94
4.4
Accept £1.35
M1
Cost of 3.6 kg is 3.6 × £ 5.94
4.4
dep
M1
= £4.86
A1
(a)
21
21
 45 or  3 or 70  45
30
2
21
Or
 21
2
(£)10.50 × 3 = (£)31.50
or 3150 (p)
(b)
[3]
[3]
M1
A1
Consistent units
Must be £ on answer line
(£)31.5 scores M1A1
B1
21 ÷ 100 × 5
M1
105
 21
100
= 1.05
A1
21 + 1.05 = 22.05
B1
The Robert Smyth School
[6]
3
The Robert Smyth School
Mathematics Faculty
Topic 6
Ratio HW 1
Innovation & excellence
6.
Potatoes cost 70p × 1.2
= 84p
M1
A1
 carrots cost 12p
0.4 kg cost 12p
1 kg costs 12
0. 4
= 30p
M1 dep
A1
[4]
7.
£
1.76
2.2
M1
= 80
A1
Accept 0.8
= 80 pence or £0.80
Unit mark (8 can be either unit)
B1
[3]
The Robert Smyth School
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