Question

At what rate of compound interest will ₹20000 becomes ₹24200 after 2 years?

Answer 1

Answer:

Step-by-step explanation:

Let , Rate per annum is r %

then ,

20000 ( 1 + r / 100 )² = 24200

( 1 + r / 100 )² = 24200 / 20000 = 242 / 200 = 121 / 100

( 1 + r / 100 )² = ( 11 / 10 )²

100 + r / 100 = 11 / 10

1000 + 10r = 1100

10r = 1100 - 1000

r = 100 / 10

∴ r = 10

∴ Rate per annum is 10%

Answer 2

Ok I have another method copy it

P = 20,000 A = 24,200. n = 2 years.

A=P[1+

100r ]

n

=20000[1+

100

r ]

2

24,200=20,000(1+100r )

2

1.21

=1+

100

r

⇒1.1=1+

100

r

100

r

=1.1−1=0.1⇒r=10%