Problem: A man buys a car for Tk. 3.00.000. The insurance for car costs him TR. 1000 for the first year. For each subsequent year the insurance costs 10% less than that for the previous year. Calculate the total cost of insurance for the first four year.
View all: NATIONAL BANK | OFFICER | RECRUITMENT QUESTION(MATH) SOLVE | 1997
Correct Answer: Tk. 3439
Explanation:
At l0% less in 2nd year.When Tk 100 less = Tk. 10
When TR 1000 less = Tk. $\frac{10\cdot100}{100}$
= Tk. 100
Insurance cost for 2nd year = 1000 — 100 = Tk 900
At 10% less in 3rd year.
When Tk. 100 then less = Tk. 10
When Tk. 900 less = Tk. $\frac{10\cdot90}{100}$
= Tk. 90
Insurance cost for 3rd year = Tk. 900 – 90
= Tk. 810
At 10% less in 4th year.
When Tk. 100 then less = Tk. 10
When Tk. 810 less = Tk. $\frac{10\cdot810}{100}$
= Tk. 81
Insurance cost for 4th year = 810 — 81 = Tk. 729
So total cost of insurance for first 4 year = 1000 + 900 + 810 + 729
= Tk. 3439
