Operations on rational numbers class 7 cbse
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Answer:
operation on rational numbers...
Rational number also follow the operation like -- addition, subtraction, multiplication and division.
let's understand it with few examples..
1.Addition
case 1:addition of two rational numbers when the denominators are same.
if there are two rational numbers a/b and c/b with same denominator then its sum will also be rational.
a/b + c/b= a+c/b
for example: 5/7 +1/7=5+1/7=6/7
case 2: addition of two rational numbers when the denominators are different.
if a/b and c/d are two rational numbers with different denominators then its sum will also be rational.
a/b+c/d=ad+cb/bd
for example: -7/10+5/-8=-7/10 - 5/8=-28-25/40=-53/40
2.Subtraction
case 1: subtraction of two rational numbers when the denominators are same.
if there are two rational numbers a/b and c/d with same denominators then its difference will also be rational.
a/b - c/d=a-c/b
for example:5/7-1/7=4/7
case 2: subtraction of two rational numbers when the denominators are different.
if a/b and c/d are two rational numbers with different denominators then its difference will also be rational.
a/b-c/d= ad-cb/bd
for example:-7/10-(-5/8) =-28+25/40=-3/40
3.Multiplication
if a/b and c/d are two rational numbers then their product a/b×c/d=ac/bd will also be a rational number.
for example:multiply 5/7 by 14/15
4.Division
if a/b and c/d are two rational numbers then their division a/b÷c/d=ad/bc will also be a rational number.
for example:divide 5/7 by 6/10