Question

which numaber should be subtracted from 13,15,and 19 such that the resultant numbers are in continuous proportion​

Answer 1

Correct option is

B

5

Let the number to be subtracted be a.

So, 13−a,25−a,55−a are in continued proportion.

If a:b::b:c, then we say that a,b,c are in continued proportion, and c is the third proportional of a and b.

Here, b

2

=ac

=>(25−a)

2

=(13−a)×(55−a)

a

2

−50a+625=a

2

−68a+715

−50a+625=−68a+715

18a=90

a=5

Hence, 5 needs to be subtracted from 13,25,55 such that they are in continued proportion.