Page 28 - SM inner class 7.cdr

.
Alternatively, we can divide as follows: = 84
.
07
85.25
5 426.25 (Moving the decimal point 1 place to right is
40 the same as multiplying by 10 .
26 10
25 84 ´ 10
.
1 2 = 84
´
.
1 0 07 10 7
25
25 =12
0 Alternatively, we can divide as follows:

12
Thus. 4 2625. ¸ 005 = 8525 7 84
.
.
7
.
Ex am ple 10. Cal cu late 84. ¸ 07. 14
.
So lu tion : 84. ¸ 07 14
0
(Move the decimal point by a place to the right)
E xercise 3.2

1. Solve the following :
(a) 2 3 100. ¸ (b) 045 5. ¸
(c) 44 3 10. ¸ (d) 1271 1000. ¸
(e) 7 3 5¸ . (f) 88 5 015. ¸ .
(g) 0 4 20. ¸

2. A side is 3.5 cm in length. The per im e ter of the poly gon is 17.5 cm. How many sides does the poly gon
have.

3. A rain fall of 0.896 cm. was re corded in 7 hours. what was the av er age amount of rain per hour?

Conversion of Units

We know about some measurement units and their relations

Length Weight Volume

1 km = 1000 m 1 kg = 1000g 1 kl = 1000 l
1 m = .001 km. 1 g = .001 kg 1 l = .001 kl

1 m = 100 cm. 1 g = 100 cg 1 l = 100 cl
1 cm = 0.1 m 1 cg = .01 g 1 cl = .01 l

1 m = 1000 mm 1 g = 1000 mg 1 l = 1000 ml
1 mm = .001 m 1 mg = .001 g 1 ml = .001

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Mathematics In Focus - 7