Page 166 - Start Up Mathematics_6

(c) Two hundred seven and fifty three hundredths

(d) Twelve and twelve thousandths
3. Write each of the following as decimals:
3 3 3
(a) 20 + 6 + (b) 300 + 30 + 3 + +
10 10 100
4 7 1 2 3
(c) 53 + + (d) 70 + 9 + + +
100 10,000 10 100 1,000

4. Express the following decimals as fractions. Reduce the fraction to its lowest term.
(a) 0.8 (b) 1.75 (c) 22.5 (d) 3.65 (e) 0.0125
5. Which is greater?

(a) 3.880 or 3.088 (b) 0.77 or 0.088 (c) 1.234 or 1.432
(d) 27.213 or 26.213 (e) 2.9302 or 2.905
6. Express the following fractions as decimals by converting the denominator to 10, 100 or
1,000 (as the case may be):
9 16 23 47 86
(a) (b) (c) (d) (e)
5 25 50 200 125

Addition of Decimals

Addition of 0.3 and 0.5

In the following figure, a strip is divided into 10
equal parts. Each part represents one-tenth or 0.1 of 0.3 0.5
the whole figure.
Three-tenths of the strip is shaded with a dark colour and five-tenths of it is shaded with a
light colour. Total shaded region covers 8 equal parts which represents 0.8 of the whole.
We have, three-tenths + five-tenths = total shaded portion of the whole

⇒ three-tenths + five-tenths = eight-tenths
i.e., 0.3 + 0.5 = 0.8

MATHS LAB ACTIVITY

Objective: Addition of decimal numbers

Material required: Chart paper, sketch pen, coloured pencils
Demonstration: Let’s add 2.13 and 1.8.

Let a big square represents 1 unit.

Represent the decimal number

2.13 by shading 2 big squares
(subdivided into 100 equal small
squares) and 13 small squares.

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