1.

 a 8 b 400 c 2000 d 4.4 e 3.26 f 0.304

 2. Round the following to the degree of accuracy stated: (a) 16 744 people at a soccer match 16700 (to the nearest hundred people) (b) A capacity of 3249 litres 3250 (to the nearest ten litres) (c) A salary of \$55,555 \$56, 000 (to the nearest thousand dollars) (d) A measurement of 9.959 metres 9.96 metres (to the nearest centimetre)

3. (a) In the table below, round each number to 1 digit and calculate.

(b) Calculate the answer accurately and round it to 4 significant figures.

 Calculation (a) Estimate (b) Accurate answer 9.1 + 5.7 9 + 6 = 15 9.1 + 5.7 = 14.8 28 x 1.9 30 x 2 = 60 28 x 1.9 = 53.2 (8.4)2 82 = 64 8.4 x 8.4 = 70.56 16.98 − (4.75 + 8.1) 20 − (5 + 8) = 7 16.98 − (4.75 + 8.1) = 4.13

4 .Round off the following numbers to the number of decimal places (d.p.) shown:
(a) 5.19 (to 1 d.p.) = 5.2
(b) 6.498 (to 2 d.p.) = 6.50
(c) 3.093 (to 1 d.p.) = 3.1
(d) 0.2949 (to 3 d.p.) = 0.295
(e) 927.295 (to 1 d.p.) = 927.3
(f) 50.94 (to 0 d.p.) = 51

5. Complete the table, by estimating the cost of each individual item to the nearest dollar and then calculating accurately.

 Purchase Estimated cost Accurate cost 4 loaves of bread at \$2.95 each 4 x \$3 = \$12 4 x \$2.95 = \$11.80 2 pies at \$1.45c each 2 x \$1 = \$2 2 x \$1.45 = \$2.90 7 biscuits at \$0.85 cents each 7 x \$1 = \$7 7 x \$0.85 = \$5.95 5 cans of drink at \$1.75 each 5 x \$2 = \$10 5 x \$1.75 = \$8.75 4 packets of chips at \$1.45 each 4 x \$1 = \$4 4 x \$1.45 = \$5.80 Totals \$35 \$35.20