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maths fun

Put a decimal point in each number at the correct place, so that these
sentences make sense for a grade 5 student.
1. I am 125 years old. 2. My weight is 2045 kg.

3. My height is 1265 cm. 4. My hand is 05 m long.
5. My middle finger is 55 cm long. 6. My foot is 135 cm long.

Place Value system of Decimal Numbers

In a whole number, the place value of a digit increases by 10 times as we move from right

to left by one place. Conversely, the place value of a digit decreases by 1 times when we
move one place from left to right. 10
1
So, we need to extend our place value chart by introducing the places for tenths 10 ,
1 1
hundredths , thousandths and so on.
100 1000
Look at the table given below, here are some decimal numbers placed in the following

place value chart.
decimal Place Value Chart
Hundreds tens Ones decimal tenths Hundredths thousandths Number
(100) (10) (1) point 1 1 1
10 100 1000
(a) 4 • 6 3 4.63
(b) 3 2 • 7 5 9 32.759

The decimal point is read as ‘point’ and the decimal part is read using the names of the digits.

We can read these numbers as:

(a) 4.63 : Four point six three Note
(b) 32.759 : Thirty-two point seven five nine The number of digits
These numbers can also be expressed in their expanded form as: in decimal part of a
(a) 4.63 = 4 ones + 6 tenths + 3 hundredths number is called the
1 1 decimal places.
= 4 + 6 × 10 + 3 × 100

6 3
= 4 + +
10 100 4 . 6 3

Clearly, in 4.63, 3
The place value of 4 = 4 ones = 4 3 hundredths = 100
6
The place value of 6 = 6 tenths = 6 = 0.6 6 tenths = 10
10 4 ones = 4
The place value of 3 = 3 hundredths = 3 = 0.03.
100

106 Mathematics-5