Page 78 - Math Smart - 7

CHAPTER 4.1

In this chapter
Understanding
Pupils should be able to:
• interpret decimal

notation and place value
Decimals

^ RECALL We see and use decimals in our everyday lives. Your weight on a digital scale
may show 32.53 kg, and a receipt may show $204.20. Do you know how much
O In the decimal 5.63, money you need to hand over based on the receipt?
what do the digits 5,
Decimals can show values between two consecutive whole numbers. It is
6, and 3 stand for?
another way to represent quantities that are parts of a whole so as to improve
State their values.
the accuracy of the quantity.
Q How do you write
A decimal point separates the whole number from the fraction part of the
36 hundredths
number.
in fraction and
decimals?
' Think and Share
Q Write 345 cents in
dollars.
In many sports, the measurement of time needs to be as accurate as
possible. For this reason, sports timing is usually recorded in hundredths of
a second.
In 2009, Usain Bolt broke the men's world record for the 100 metre sprint.
His time was 9.58 seconds.
If an athlete ran a faster time, even if it was only one hundredth (0.01) of
a second faster, they would become the new record holder.

How many decimal places are used to measure Usain's 100 metre sprint?

Decimal notation

Spotlight A decimal Is a fraction whose denominator is a power of 10.

0.4 (4 tenths) =
Numbers within the
decimal system may
• be whole numbers 0.09 (9 hundredths) =
100 decimal point
(e.g. 327)
A decimal point is used to separate the whole number
• contain parts of a
from the fraction part of the number. 327! 251
whole (e.g. 327.25)

UNIT 4 Decimals