Question

If the interest on Rs.2400 is more than the interest on Rs.2000 by Rs.60 in 3 years at the same rate percent; find the rate.

Answer 1

In first case :

P = Rs.2400

R = x% (Assume)

T = 3 years

Interest = `("P"xx"R"xx"T")/100`

= Rs.`(2400xx"x"xx3)/100`

= Rs.72x

In second case :

P = Rs.2000

R = x% ....(Rate same as in first case)

T = 3 years

Interest = `("P"xx"R"xx"T")/100`

= Rs.`(2000xx"x"xx3)/100`

= Rs.60x

According to the statement,

72x = 60x + 60

⇒ 72x − 60x = 60

⇒ 12x = 60

⇒ x =`60/12`

⇒ x = 5

∴ Rate = 5%