Express
as a rational number with denominator
(i) 20 (ii) -30 (iii) 35 (iv) -40
For a fraction, 
Where, n ≠ 0
(i) We have to express 
as a rational number with denominator 20.
In order to make the denominator 20, multiply 5 by 4.
Therefore,
(ii) We have to express 
as a rational number with denominator -30.
In order to make the denominator -30, multiply 5 by -6.
Therefore,
(iii) We have to express 
as a rational number with denominator 35.
In order to make the denominator 35, multiply 5 by 7.
Therefore,
(iv) We have to express 
as a rational number with denominator -40.
In order to make the denominator 20, multiply 5 by -8.
Therefore,
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