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Write these numbers in a place-value table: b) Check that your answers are reasonable by
estimating and comparing your estimate
a) 49.6 b) 29.69 c) 2.04
to your answers in a).
d) 0.140 e) 340.05 f) 1794.32
c) Mei paid S$30.50 for material to make
g) 600.294
cushions. How much did the material for
each cushion cost?
In the number
a) 4.1432, which digit Is in the hundredths Peggy worked a total of 47.28 hours over 6
place? days.
b) 3.876, what is the value of the digit 8? a) What Is the average number of hours that
c) 5.084, what is the place value of the Peggy worked per day?
digit 5? b) How many hours will Peggy work if she
6 Write two ones and thirty-four hundredths In works 8 days at the same average
numerals. rate?
O Nick's three best practice times for the 100-m Tony has 5.6 kg of coffee. He packs the coffee
sprint are as follows: into 8 jars of equal mass.

13.95 seconds 13.08 seconds 13.69 seconds a) What Is the mass of coffee in each jar?
a) Write Nick's practice times from fastest to b) If each jar has a mass of 120 g when it Is
slowest. empty, what is the total mass of one jar of
b) What is the difference between Nick's coffee?
fastest practice time and his slowest c) What is the total mass of 8 jars of coffee?
practice time?
<E) Use estimation to explain which of the
Subtract 38.45 from 64.12 and round to the
calculations Is incorrect.
nearest tenths. The answer is .
a) 15.2X6.2 = 94.24
o Calculate.
b) 34.1X2.9 = 9.88
a) i) 152-f 100 =
c) 21.7-f 4.1 =52.93
ii) 24.5-r 100 =
ill) 30.21 -r 100 = <D *Challenge! A classroom wall is 7.8 m long. A
classroom desk is 170 cm long. Estimate how
b) I) 2 X 2.4 =
many classroom desks will fit along the wall.
ii) 4 X 2.4 =
ill) 5 X 2.4 =
170 cm
i) 1.2 = 3.6
ii) 3.71 =11.13
\
lii) 2.04 = 6.12
Mei makes curtains and cushions. She uses
0.5 m of material to make a cushion, 1.55 m of
material to make a short curtain and 2.25 m
of material to make a long curtain,
a) Calculate the length of material Mei will
need to make
I) 2 cushions,
ii) 3 long curtains,
iii) 4 short curtains.

UNIT 4 I Decimals