a sum of money becomes 8/5 of itself in 5 years at a certain rate of simple intrest. Find the rate of intrest

12%

Explanation:

It would be easier to assume a certain number when answering such questions.

Assume for instance, that the sum of money is $1,000.

In 5 years it increased by 8/5:

= 1,000 * 8/5

= $1,600

In 5 years this figure increased to $1,600. Increase was:

= 1,600 - 1,000

= $600

Simple interest is the same every year so the interest per year was:

= 600/5

= $120

Rate = 120 / 1,000

= 12%

Faster method.

= 8/5

= 1.6

Sum increased by 1.6 which means interest over 5 years was:

= 1.6 - 1

= 60%

Rate = 60%/ 5 years

= 12%

what are you asking? this is gibberish.

the rigid outer part of the earth, consisting of the crust and upper mantle is the lithosphere.     answer   crust and outer part of the mantle.