Area of Circles and Composite Shapes

Worksheet answers

Worksheet 1: Programme Questions
1. 8 inches
2. A = r²
3. Jamie's
4. 14cm
5. 6 million
6. 3.142
7. m²
8. Rectangle
9. Semi-circles
10. 72m

Worksheet 2: Tick or Trash

Question 1

Student B is correct. Student A has failed to identify two appropriate rectangles.

Question 2

Student A is correct. Student B has wrongly calculated ( x 5.1)² and has given the wrong units in the answer.

Worksheet 3: Exam Practice Questions

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) p x 12 = 37.7cm

(b)	12 x	130	;
		100
	12 +	12 x	130	= 15.6cm
			100

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Question 2

(a) For example, 2.23m can be measured: p normally give to 2 decimal places
(b) 1st is too accurate: cannot be measured. 2nd is not accurate: not near enough to 7m

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Question 3

(a) 40 + 40 + 50 + 70 = 200
(b) i) 40 x 40 = 1600m²
ii) (40 x 30) ÷ 2 = 600m²

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Question 4

(a) Radius is 2.8cm. 2.8 x 10 = 28km
(b) x '(a)'² = 2463 km²

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Question 5
A = r² = x 35 x 35 = 3846.5 (if = 3.14), 3850 (if = 22 ÷ 7), 3848.4 (if = button)
70 x 70 = (4900) '4900' - '3850'
A = 1050cm²

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Question 6

(a) Trapezium

(b) 5.3 x 1.2 + ½ x 0.9 x 5.3

OR ½ (1.2 + 2.1) x 5.3

Area = 8.745 m²

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Question 7

(a) x 0.65 x 0.65 = 1.33m²
(b) D = 5 ÷ = 1.59m

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Question 8

(a) 4 + 4 + 2 + 1 = 11cm²
(b) i) 0.5 x x 10 (= 15.7…)
'15.7…' + 10 = 25.7cm
ii) 0.5 x x 5 x 5 = 39.3cm²

Notes:
(a) M1 for splitting shape
A1 cao for 11
(b) M1 for 0.5 x p x 10 or 15.7 seen
M1 (dep) for + 10
A1 cao for 25.7 or better
M1 for 0.5 x ^p x 5 x 5
A1 cao for 39.3 or better

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Question 9

Various methods
Answer = 37m²

Notes:
M1 division into rectangles or square tiles (could be implied from working, or shown on the diagram)
M1 l x b (at least once, or implied from working)
Eg for M2 sight of 10, 27 or 25, 12 if shape not shown divided
A1 37 cao
B1 (indep) for m²

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Question 10

(Area of circle =) 10² (oe)
= 100p (oe)
(Area of triangle =) ½ x 12 x 16
= 96
(Shaded area =) 10² - (½ x 12 x 16)
Answer = 218cm²

Notes:
M1
A1 cao (accept 314 or better)
M1 (implied if later work correct)
A1 cao
M1 dep on at least one of the two previous M1's gained.
A1 cao (accept uncorrected)