Question

5.
20 copies of a book can be purchased for a
certain sum payable at the end of 6 months
and 21 copies for the same sum in ready
cash. Find the rate of interest.​

Answer 1

Answer:

∴ The rate is 10%

Step-by-step explanation:

Number of copies purchased = 20

Number of months = 6 months

Same number of copies = 21 copies

Rate of interest = ?

Let we assume be the price of 1 book = X

For 20 books payable amount after 6 months = Principal × ( Rate × Time Period + 100 / 100 )

Since 20 books paid in cash total price is = 21X

Cash price of 21 copies is same as interest of 20 copies

So, 20X + ( X × Rate / 10 ) = 21X

X = ( X × Rate / 10 )

X = 10%

∴ The rate is 10%

Hope it helps!

Pls mark as brainliest : )