Question

A certain amount is double in 8 yar. then when is triple with same intrest

Answer 1

Hi , Aakanksha  hope this will help u

Let the principle [P]=100.

Then amount[A] will be 200.

Interest [SI]= 100

Time [T]= 8 yrs

Rate [R]=?

SI=P*R*T/100

⇒100=100*R*8/100

⇒100*100/100*8=R

⇒100/8=R

Now sum should be 3 times means  p*3=100*3= 300

⇒ SI on 100 is [A-P]= [300-100]= 200.

⇒SI=P*R*T/100

⇒200=100*100/8*T/100

⇒200*8/100=T

⇒16= T

In 16 years sum will become 4 times the principle.  ANS