anonymous
  • anonymous
The compound interest on a certain sum for 2 years is Rs 412 and the simple interest is Rs 400. What is the rate of interest per annum?
Mathematics
  • Stacey Warren - Expert brainly.com
Hey! We 've verified this expert answer for you, click below to unlock the details :)
SOLVED
At vero eos et accusamus et iusto odio dignissimos ducimus qui blanditiis praesentium voluptatum deleniti atque corrupti quos dolores et quas molestias excepturi sint occaecati cupiditate non provident, similique sunt in culpa qui officia deserunt mollitia animi, id est laborum et dolorum fuga. Et harum quidem rerum facilis est et expedita distinctio. Nam libero tempore, cum soluta nobis est eligendi optio cumque nihil impedit quo minus id quod maxime placeat facere possimus, omnis voluptas assumenda est, omnis dolor repellendus. Itaque earum rerum hic tenetur a sapiente delectus, ut aut reiciendis voluptatibus maiores alias consequatur aut perferendis doloribus asperiores repellat.
chestercat
  • chestercat
I got my questions answered at brainly.com in under 10 minutes. Go to brainly.com now for free help!
goformit100
  • goformit100
"Welcome to OpenStudy. I can guide regarding this useful site; ask your doubts from me, for it you can message me. Please use the chat for off topic questions. And remember to give the helper a medal, by clicking on "Best Answer". We follow a code of conduct, ( http://openstudy.com/code-of-conduct ). Please take a moment to read it."
anonymous
  • anonymous
k thanks
kropot72
  • kropot72
Let P be the principal and r be the rate of interest per annum expressed as a decimal. The amount of simple interest is given by \[400=2\Pr\ ...........(1)\] Rearranging equation (1) to give the principal in terms of r gives: \[P=\frac{400}{2r}\ ..........(2)\] The amount of compound interest is given by \[412=P(1+r)^{2}-P=P[(1+r)^{2}-1]\ .......(3)\] Substituting the value for P from equation (2) into equation (3) gives \[412=\frac{400}{2r}[(1+r)^{2}-1]\ .......(4)\] Rearranging the right hand side of equation (4) to remove the inner parenthesis gives \[412=\frac{400}{2r}(2r+r ^{2})\ ..........(5)\] Now just solve equation (5) to find r, the decimal rate of interest.

Looking for something else?

Not the answer you are looking for? Search for more explanations.