Page 21 - SM inner class 7.cdr

53 æ ö
5
Ex am ple 17. Di vide by 5. = ´ ç ÷
2
10 è ø
3
So lu tion : Write fraction and whole number Multiply whole number with the numerator
in di vi sion ex pres sion and we get: and keep the denominator same & we get;
æ 53 ö (2 5 )
´
ç ÷ ¸ 5 =
è 10 ø 3
Find the Reciprocal of whole number i.e. 5 Solve the bracket and we get;
1 10
Reciprocal of 5 = =
5 3

æ 53 ö æ 3 ö æ 10 ö 1
Multiply fraction ç ÷ with the reciprocal of Hence, 2 ¸ ç ÷ = ç ÷ = 3
è 10 ø è 5ø è 3 ø 3
whole number (calculated above) and we get; 77
Ex am ple 19 : Solve 10 ¸ .
1
æ53 ö æ ö 86
= ç ÷ ´ ç ÷
5
è10 ø è ø
So lu tion : Write whole number and fraction
Multiplication of numerators, divided by, in di vi sion ex pres sion and we get:
multiplication of denominators and we get; æ 77 ö
1
(53 ´ ) 10 ¸ ç ÷
= è 86ø
(10 ´ )
5
77
Solve the Brackets and we get; Find the Reciprocal of fraction i.e.
86
53
= 77 86
50 Reciprocal of =
86 77
53 53 3
Hence, ¸ 5 = =1
10 50 50 Multiply whole number with the reciprocal of
fraction (calculated above) and we get;
2. Division of Whole Number by Fraction
86
Steps of division are: =10 ´
77
Step 1 : Find re cip ro cal of given frac tion
Multiply whole number with the numerator
Step 2 : Multiply given whole number with
re cip ro cal of given frac tion (cal cu lated in step 1) and keep the denominator same & we get;
Step 3 : Multiply whole number with the = (10 ´86 )
nu mer a tor and keep the de nom i na tor same 77
3 Solve the bracket and we get;
Ex am ple 18 : Solve 2 ¸
5 860
=
So lu tion : Write whole number and fraction 77
in di vi sion ex pres sion and we get: æ 77 ö æ 860 ö 13
=
æ 3 ö Hence, 10 ¸ ç ÷ = ç ÷ 11
2 ¸ ç ÷ è 86ø è 77 ø 77
è 5ø
3. Division of Fractional Number by
3
Find the Reciprocal of fraction i.e. Another Fraction Number
5
3 5 Under this division, we multiply one fraction
Reciprocal of =
5 3 number with reciprocal of another fraction
number.
Multiply whole number (i.e. 2) with the
reciprocal of fraction (calculated above) and we Following examples further elaborates this
get; method :

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Mathematics In Focus - 7