Question

Abhishek invested some amount for 3 yrs at rate of 16(2/3)%per annum at CI. The difference of CI obtaine
only on 3rd year and C.I. obtained only on second year is Rs 210. Find the amount invested by Abhishek?
1. Rs 6,220
2. Rs 6,480
3. Rs 8,420 4. Rs 7,420 5. Rs 8,240
​

Answer 1

Solution :-

Let us assume that, the amount invested by Abhishek is Rsx.

we know that, when rate of interest is compounded annually ,

• A = P[1 + (R/100)]^T

given that,

Rate = 16(2/3)% = (50/3)% = (1/6)

so,

→ Amount after 1 year = x * (1 + 1/6) = Rs.(7x/6)

then,

→ CI of second year only = (1/6) of Amount after 1 year = (1/6) * (7x/6) = Rs.(7x/36)

now,

→ Amount after 2 years = Amount after 1 year + CI of second year = (7x/6) + (7x/36) = (49x/36) .

then,

→ CI obtained only on 3rd year = (1/6) of Amount after 2 years = (1/6) * (49x/36) = Rs.(49x/216) .

A/q,

→ (49x/216) - (7x/36) = 210

→ (49x - 42x)/216 = 210

→ 7x / 216 = 210

→ x = 216 * 30

→ x = Rs.6480 (Ans.2)

Learn more :-

CI in 2yr is Rs. 1600 and in 3 yrs it will be Rs. 1700. Find the rate of interest.

brainly.in/question/32463301

Answer 2

Answer:

6480

Step-by-step explanation:

let us assume that

1st investment equal to 540rs

the CI pattern of 540 in 3 years is

540----630---735---857.5

the difference between 630 and 735 is 105

''. ''. ''. 735 and 857.5 is 122.5

there fore 122.5 -105 =17.5

17.5 × X =210 × 540

X= 6480