Page 161 - Start Up Mathematics_6

55
(b) 55 mm = cm = 5.5 cm
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212
(c) 212 mm = cm = 21.2 cm
10
2
(d) 5 cm 2 mm = 5 cm + cm = (5 + 0.2) cm = 5.2 cm
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Example 7: Between which two whole numbers on a number line do the given numbers lie?
Which of these whole numbers is nearer to the number?

0 1 2 3 4 5 6 7 8 9 10 11 12

(a) 0.4 (b) 5.9 (c) 3.7 (d) 4.5
Solution: Number Lies between Near to whole number

(a) 0.4 0 and 1 0
(b) 5.9 5 and 6 6
(c) 3.7 3 and 4 4
(d) 4.5 4 and 5 Equidistant from 4 and 5

Example 8: Represent the decimal numbers 0.3, 1.3, 1.5 and 1.9 by points P, Q, R and S on a
number line.
P Q R S
Solution:
0 0.3 1 1.3 1.5 1.9 2

Example 9: Write the decimal number represented by the points P, Q, R, S and T on the number
line given below. Write the point equidistant from S and T.

0 P Q 1 R 2 S T 3
Solution: P = 0.1; Q = 0.7; R = 1.9; S = 2.4; T = 2.6

The decimal representation of a point equidistant from S and T is 2.5.
Example 10: (a) The length of Joseph’s pencil is 9 cm 7 mm. What will be its length in cm?

(b) The length of a line segment is 112 mm. Express its length in cm.
7
Solution: (a) The length of Joseph’s pencil = 9 cm + 7 mm = 9 cm + cm
10
= 9 cm + 0.7 cm = 9.7 cm
112
(b) The length of line segment = 112 mm = cm = 11.2 cm
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Hundredths

Let’s represent a unit by the following figure. The shaded part in Fig. (a)
1
represents one-hundredth of the whole unit. In fractions, it is written as 100 .
Its equivalent in decimals is 0.01.

Fig. (a)

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