A sum of Rs. 210 was taken as a loan. This is to be paid back in two equal installments. If the rate of the interest be 10% compounded annually, then the value of each installment is:
A. Rs. 121
B. Rs. 127
C. Rs. 210
D. Rs. 225
Answer: Option A
Solution (By Examveda Team)
Let X = equal installment at the end of one year( rate% annually) . Now 1st year, P =210, Interest = $$\frac{{{\text{PTR}}}}{{100}}$$ = 210 * 0.1 = 21. Let X is to be paid as an equal installment. Now, at the beginning of 2nd year, P = 210 + 21 - X, Interest at the end of 2nd year, = (231 - X) * 0.1 = 23.1 - 0.1X. Hence,total installment, 2X = 210 + 21 + 23.1 - 0.1X, X = $$\frac{{{\text{254}}{\text{.1}}}}{{2.1}}$$ = 121.This Question Belongs to Arithmetic Ability >> Interest
P₁ : A₁ = (10 : 11)×11 = 110 : 121
P₂ : A₂ = 100 : 121
Now, (110 + 100) = 210 units ≡ Tk.210
⇒121 units ≡ Tk.121 (Ans.)
Solved by : Mostafa kamal Abir
⇒(400 + 420) i.e 820 units ≡ Tk.1,640
rate = 10% = 110/100=11/10
and given paid in two equal installments so square of 11 i.e. 121 so 121 is answer