Question

A rational number can be expressed as a terminating decimal if its denominator has factors :- a. 4 or 5, b. 2 or 3, c. 2 or 3 or 5 d. 2 or 5 how we can solve this & what is the meaning of terminating decimal ?

Answer 1

d. 2 or 5 If a no has factors in the form of 2 or 5. Then it is a terminating decimal

Answer 2

Any rational number its denominator is in the form of 2^m*5^n,where m,n are positive integer s are terminating decimals. Examples 1)15/8= 15/(2*2*2)= 15/2^3 = (15*5^3)/(2^3*5^3) = 1875/1000=1.875 2) 21/5= (21*2)/(5*2)=42/10=4.2 3)31/20= 31/(2*2*5)= (31*5)/(2*2*5*5) =155/100=1.55