M May

Write each (i) to the nearest ten

1. 83572. 80 5483. 245 6324. 345. 764 799

(ii) to the nearest hundred

6. 26.837. 425.288. 816.49. 95.8

10. 2 555.5

= 8360= 80 550

= 245 630= 30

= 764 800= 30

= 430= 820= 100

= 2 560

(to nearest ten) = 8400 (to nearest hundred)= 80 500

= 245 600= 0

= 764 800= 0

= 400= 800= 100

= 2 600

M May

Write each (i) to the nearest tenth

1. 42.572. 157.933. 4.68354. 27.065. 2 473.888

(ii) to the nearest whole

6. 26.837. 425.288. 816.499. 95.807

10. 2 555.555

= 42.6= 157.9

= 4.7= 27.1

= 2 473.9= 26.8

= 425.3= 816.5

= 95.8= 2 555.6

(to nearest tenth) = 43 (to nearest whole)= 158

= 5= 27

= 2 474= 27

= 425= 816= 96

= 2 556

M May

56 000 000

2 significant figures

45 0.0062

3 significant figures

378 000 27.3 0.005 32

to nearest 1000 to nearest tenth to nearesthundred thousandthto 1 dec pl

to 5 dec pl

to nearestmillion to nearest

wholeto 4 dec pl

56.0

to nearest tenth

3050

to nearest ten

0.004 07

to 5 dec pl

7002

4 significant figures

5.308

to 3 dec pl

M May

Round each of the following to 3 significant figures

34 629 73 579 1347 45.666 2.8369

173.92 0.004683 9044 0.04968 12.345

0.000 083 76 47.73 31.655 919.9 2547

Round each of the following to 2 sig fig

8 776 341 31.793 258.6 91 832 428

0.085 726 129.3 2040 1.036 35.67

34 600 73 600 1350 45.7 2.84

174 0.00468 9040 0.0497 12.3

0.000 083 8 47.7 31.7 920 2550

8 800 000 32 260 92 000 430

0.086 130 2000 1.0 36

M May

EE or Exp on scientific calculator

in place of x 10n 5.3 03

on display means 5.3 x 103

5.3 x 103 x 2.7 x 104

= 5.3Exp3 x 2.7Exp41.431 x 108

5 x 103 x 3 x 104

= 5 x 3 x 103 x 104

= 15 x 107

= 1.5 x 10 x 107

without calculator / estimate 2.83 x 102 x 9.167 x 103

estimate 3 x 9 x 102 x 103

27 x 105 = 2.7 x 106

= 2.594261 x 106

= 2.59 x 106 to 3 sig fig= 1.5 x 108

M May

50% = 0.50 =

25% = 0.25 =

20% = 0.20 =

10% = 0.10 =

1% = 0.01 =

13% = 0.13

1/2 ÷ 2

1/4 ÷ 4

1/5 ÷ 5

1/10 ÷ 10

1/100 ÷ 100

…% of ………

331/3% = 1/3 ÷ 3

13% of £67= 0.13 x 67= 8.71

50% of £658

= 658 ÷ 2

= 329

1% of 7382 kg= 7382 ÷ 100= 73.82

M May

35 marks out of total 56

3556

x 10035 ÷ 56 x 100

= 62.5%

Item costs £45 and sells for £54.Express the profit as a percentage of the cost price.

S P = 54C P = 45

Profit = 9 9 ÷ 45 x 100

945

x 100 = 20 %

So Pupil’s mark was 62.5%

So Profit was 20% of the cost price.