Volume of Prisms

Worksheet Answers

Worksheet 1: Programme Questions

1. Cone
2. Maths 4 Real
3. Cross-section
4. Square and trapezium
5. Cubic metres (m³)
6. 4m or 400cm
7. 1 million
8. 3.8 million
9. 1/2 base x height
10. Regular hexagon

Worksheet 2: Tick or Trash

Question 1

Student A is correct. Student B has omitted multiplying by the length of the prism.

Question 2

Student A is correct. Student B has assumed that the hole is a cube.

Worksheet 3: Exam Practice Questions (Edexcel)

This is a selection of past exam questions from Edexcel, targeted at the middle ability range. You can use the sequence as it stands or select individual questions to suit your needs.

Below is the mark scheme for each question, which may help you to see how marks are allocated and what the examiner is especially looking for. The mark schemes use the following abbreviations:

oe	or equivalent
cao	correct answer only
ft	follow-through marks
dep	dependent
indep	independent
M	method marks
A	accuracy marks
B	benefit-of-doubt mark
SC	special case

Question 1

(a) 30 x 30 x 20 = 18 000cm³
(b) 30 x 30 x 21.6 = 19 440
(19 440 - 'a') ÷ 'a' x 100
= 8%
or (21.6 - 20) ÷ 20 x 100
= 8%

Notes:
(a) M1 for 30 x 30 x 20
A1 cao
(b) M1 for 19 440 or 30 x 30 x 21.6
30 x 30 x 1.6 or 1440 or
21.6 - 20 x 100
    20
or (21.6 - 20) x 100
A1 cao

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Question 2

(a)	(1.7 + 2.3)	x 1.3 = 2.6m2
	2

or

1.7 x 1.3 + 0.6 x	1.3	= 2.6m2
	2

(b) 'a' x 1.5
Accept 'a' rounded
= 3.9m³
(c) 'b' x 4300 + 650
Accept 'b' rounded
= 17 420kg

Notes:
(a) M1 for correct substitution
A1 cao
Alternative
M1 (M0 if no/2)
A1 cao
(b) M1 for 'a' x 1.5
A1 ft
(c) M1 for 'b' x 4300
M1 for + 650 (dep)
A1 cao

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Question 3

(a) 20 x 10 = 200cm²
(b) i) 20 x 10 x 15 = 3000cm³
ii) 3000 ÷ 1000 = 3 litres

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Question 4

1 x 4 x h = 7
2

h = 3.5cm
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Question 5

1 (2 + 4) x 2 x 10
2

= 60cm³

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Question 6

3.14 x 4.3 x 4.3 x 26.3 = 1526.9
x 4.3 x 4.3 x 26.3 = 1527.7
3.142 x 4.3 x 4.3 x 26.3 = 1527.9

= 1530cm (3sf)

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Question 7

(a) r²h = x 8² x 20 = 4021… cm³
(b) 16 x 16 x 16 = 4096cm³ (a) + '4096' = 8117cm³
(c) i) 7.5cm
ii) 8.5cm