Rounding, Estimation & Bounds (Cambridge International IGCSE Mathematics): Exam Questions

Write 0.3728 correct to 1 decimal place.

The height, $h$ metres, of a tower is 128m, correct to the nearest metre. Complete the statement about the value of $h$.

..................less-than or slanted equal to h less than.............

Write 867 correct to the nearest ten.

The length, $l$ cm, of a pencil is 18cm, correct to the nearest centimetre.

Complete the statement about the value of$l.$

................... less-than or slanted equal to l less than ...................

Write 849.481 correct to 1 decimal place.

Write 97.4236 correct to 3 decimal places.

Write 3.72194 correct to 3 decimal places.

Write 8379 correct to the nearest hundred.

Write 6789 correct to the nearest 100.

Write 6789 correct to 3 significant figures.

The mass, $m$ kilograms, of a horse is 429kg, correct to the nearest kilogram.

Complete this statement about the value of $m$.

..................... ⩽ $m$ < .....................

Write 8473 correct to the nearest ten.

Write 16.086 correct to 2 decimal places.

Write 3.058 correct to 3 significant figures.

Genaro measures the length, $l$ cm, of his desk as 120 cm, correct to the nearest centimetre.

Complete the statement about the value of $l$.

...................... less-than or slanted equal to l less than .....................

Round 1850 to 2 significant figures.

By writing each number correct to 1 significant figure, estimate the value of

$\frac{37.8\times13.2}{28.5+22.1}$

You must show all your working.

The height, $h$ metres, of a tower is 76.3 m, correct to 1 decimal place. Complete this statement about the value of $h$.

.................... $\text{less} - \text{than} or \text{slanted} \text{equal} to h <$ ....................

By rounding each number correct to 1 significant figure, estimate the value of

$\frac{71\times32.4}{4.8^{2}}$

You must show all your working.

Calculate $\sqrt[3]{40}$

Give your answer correct to 4 decimal places

By rounding each number correct to 1 significant figure, show that an estimate for this calculation is 20.

$\frac{9.78+31.562}{0.381\times5.09}$

Write 0.047883 correct to 2 significant figures.

Write 6.8167 correct to 3 significant figures.

The amount of fuel,$t$ litres, in a boat’s fuel tank is 135 litres, correct to the nearest litre.

Complete the statement about the value of $t$.

..................... less-than or slanted equal to t less than....................

Marco watched 25 boats enter a port, of which 9 had a mast. There are a total of 200 boats in the port.

Calculate an estimate of the number of boats in the port that have a mast.

$T=\frac{49.2-9.59}{4.085\times2.35}$

By writing each number correct to 1 significant figure, work out an estimate for $T$. You must show all your working.

The length,$l$cm, of a line is 18.3 cm, correct to the nearest millimetre.

Complete this statement about the value of $l$.

.................... less-than or slanted equal to l less than..................

The length, $l$cm, of a sheet of paper is 29.7 cm, correct to the nearest millimetre.

Complete this statement about the value of$l$.

.............................. less-than or slanted equal to l less than ..............................

The mass, $m$ grams, of a banana is 115 g, correct to the nearest 5 g.

Complete the statement about the value of $m$.

............................ less-than or slanted equal to m less than ............................

By rounding each number correct to 1 significant figure, estimate the value of $\sqrt{\frac{90006}{10.01^{2}}}$

You must show all your working.

The amount of water, $w$ litres, in a jug is 1.5 litres, correct to the nearest 0.1 litre.

Complete this statement about the value of $w$.

$...................\leq w<...................$

The length, $p$ cm, of a pencil is 9.8cm, correct to 2 significant figures.

Complete the statement about the value of $p$.

.................... less-than or slanted equal to p less than ....................

The length of a truck, $L$ metres, is 8.2m, correct to 1 decimal place. Complete this statement about the value of$L$.

..................... less-than or slanted equal to L less than .....................

$p=\frac{1.6+9.6^{2}}{5.9-4.3}$

By writing each number correct to 1 significant figure, work out an estimate for $p$. You must show all your working.

Zach goes on holiday.

The mass, $m$ kilograms, of his suitcase is 23.5 kg, correct to the nearest 500 g. Complete this statement about the value of $m$.

...................... ≤m< ......................

Write 0.046875 correct to 2 significant figures.

Without using a calculator, estimate, by rounding each number correct to 1 significant figure,

$\frac{\sqrt{104.3}}{8.72-7.389}$

You must show all your working.

The width, $w$ metres, of a room is 4.2 metres, correct to the nearest 10 centimetres.

Complete this statement about the value of $w$.

.............. less-than or slanted equal to w less than ..............

The length, $l$ metres, of a garden is 78.5 metres, correct to the nearest half metre.

Complete this statement about the value of $l$.

.................... less-than or slanted equal to l less than ....................