Number 5
2 marks · EasyA length is measured as 40 cm, correct to the nearest cm.
Write down the lower and upper bounds of the measurement.
Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.
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Lower bound: 39.5 cm Upper bound: 40.5 cm
Also accept: Lower bound 39.5 cm, upper bound 40.5 cm; 39.5 ≤ length < 40.5
Common mistakes: 39 cm and 41 cm; 39 and 40; 40 and 41
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Marking points
B1 · 1 mark · Correct lower bound: 39.5 cm
B2 · 1 mark · Correct upper bound: 40.5 cm
Worked solution
The measurement is to the nearest cm. Lower bound is 40 - 0.5 = 39.5 cm. Upper bound is 40 + 0.5 = 40.5 cm.