Printable · GCSE Higher · ages 14-16

Limits of accuracy and bounds worksheet — GCSE Higher

Fifteen questions on "limits of accuracy and bounds" — DfE statement N16. Print it, or print three versions so neighbours cannot copy by letter; the key gives the letter for each version.

part Higher

VersionsA only A + B A + B + Csame questions, different order

AnswersQuestions only With answer key Key only

CalculatorMixed Non-calculator (Paper 1)Calculator (Papers 2 and 3)

New sheet

Limits of accuracy and bounds worksheet — GCSE Higher

Maths · GCSE Higher · N16 · Limits of accuracy and bounds · 15 questions

MathsUKwww.geekhero.co.uk

1.A machine fills bags of sugar and shows the mass of each bag to the nearest 10 g. A checker rejects any bag whose actual mass is less than 996 g. One bag shows a mass of 1,000 g on the machine. Decide whether this bag could be rejected, and give a reason for your answer.
(a)No — the actual mass is exactly 1,000 g
(b)Yes — the actual mass could be as low as 995 g
(c)Yes — the actual mass could be as low as 990 g
(d)No — the actual mass is at least 999.5 g
2.A lift has a safe working load of 500 kg. Four people get in the lift and the lift's display records their total mass as 493 kg, correct to the nearest kg. Decide whether the four people are definitely within the safe working load.
(a)No — 493 kg is only an estimate, so it may be over 500 kg
(b)Cannot be decided without the exact total
(c)Yes — the greatest possible total is 493.5 kg, under 500 kg
(d)No — the true total could be as high as 498 kg
3.A rope is measured as 15 m, correct to the nearest metre. Write down the error interval for the true length, l, of the rope.
(a)14.5 < l < 15.5
(b)14.5 ≤ l < 15.5
(c)14 ≤ l < 16
(d)14.5 ≤ l ≤ 15.5
4.A car travels 100 km, correct to the nearest km, in a time of 2 hours, correct to the nearest 0.1 hour. Work out the average speed, in km/h, to the greatest degree of accuracy the bounds can guarantee.
(a)49 km/h
(b)48.54 km/h
(c)52 km/h
(d)50 km/h
5.A bag of flour is labelled 1.5 kg, correct to the nearest 0.1 kg. The true mass of the flour is m kg. Which inequality gives all the possible values of m?
(a)1.4 ≤ m < 1.6
(b)1.45 ≤ m < 1.55
(c)1.45 < m ≤ 1.55
(d)1.45 ≤ m ≤ 1.55
6.p = 24 and q = 6, each correct to the nearest integer. Work out the greatest degree of accuracy to which p ÷ q can be guaranteed correct.
(a)the nearest whole number
(b)it cannot be given to any degree of accuracy
(c)the nearest 0.1
(d)the nearest 10
7.The number of visitors to a museum on Saturday is given as 1,800, correct to the nearest 100. Which of these could not be the actual number of visitors?
(a)1,850
(b)1,799
(c)1,760
(d)1,750
8.Postage on a parcel is calculated as £4.60, correct to the nearest 20p. Which of these could not be the actual cost of the postage?
(a)£4.55
(b)£4.50
(c)£4.65
(d)£4.80
9.The density of a metal is calculated using density = mass ÷ volume. A sample has a mass of 156 g, correct to the nearest gram, and a volume of 12 cm³, correct to the nearest cm³. Work out the minimum possible density, in g/cm³.
(a)13
(b)13.52
(c)12.44
(d)12.52
10.A courier's van has a weight limit of 850 kg for its parcels. The driver's display shows the total mass of the parcels loaded as 850 kg, correct to the nearest 5 kg. Decide whether the parcels are definitely within the weight limit.
(a)Yes, the true mass is at least 847.5 kg and at most 850 kg
(b)No, the true mass could be as high as 852.5 kg
(c)Yes, the display reads 850 kg, which is not above the limit
(d)No, 850 kg on the display rounds up to 855 kg
11.c = 50, correct to the nearest 10. d = 18, correct to the nearest whole number. Work out the upper bound of c − d.
(a)37.5
(b)27.5
(c)36.5
(d)26.5
12.Ava measures a metal rod and records its length as 15 cm, correct to the nearest centimetre. Ben measures the same rod and records its length as 14.8 cm, correct to the nearest 0.1 cm. Decide whether both records can be correct, and give a reason for your answer.
(a)No, because 14.8 cm is not the same length as 15 cm
(b)Yes, because 14.8 cm rounds to 15 cm to the nearest cm
(c)No, because 14.8 cm rounds to 14 cm to the nearest cm
(d)Yes, because 14.8 cm rounds to 15.0 cm to 1 decimal place
13.A plank has length a = 12 cm and a second plank has length b = 7 cm, each correct to the nearest centimetre. Work out the upper bound of a + b.
(a)19.5
(b)20
(c)18
(d)21
14.A garden path is measured by Jon as 12 m, correct to the nearest metre, and by Mia as 12.6 m, correct to the nearest 0.1 m. Which statement about the two measurements is correct?
(a)They cannot both be describing the same path
(b)Jon's measurement must be wrong
(c)Mia's measurement must be wrong
(d)They must both be describing the same path
15.The rainfall in a town during April is recorded as 62.4 mm, correct to 1 decimal place. Write down the error interval for the actual rainfall, r mm.
(a)62 ≤ r < 63
(b)62.35 ≤ r ≤ 62.45
(c)62.35 ≤ r < 62.45
(d)62.3 ≤ r < 62.5

Build your own mix at the worksheet builder.