If a person borrows money at a compound interest for 3 years, then calculate the amount to be returned in 3 years. I. After 5 years, Rs. 800 has to be paid as simple interest. II. The interest is rated at 5% per annum. III. The amount to be paid after 3 years as simple interest is equal to 6 times the amount when it was borrowed. Which statement(s) is/are required to answer the question?

If a person borrows money at a compound interest for 3 years, then calculate the amount to be returned in 3 years. I. After 5 years, Rs. 800 has to be paid as simple interest. II. The interest is rated at 5% per annum. III. The amount to be paid after 3 years as simple interest is equal to 6 times the amount when it was borrowed. Which statement(s) is/are required to answer the question? Correct Answer Statement I and either statement II or statement III together are sufficient to answer the question.

Considering statements I and II together

S.I. after 1 year will be 800/5 = Rs. 160

r = 5% and t = 1 year

⇒ P = 160 × 100/5 = 3200

∵ We have Rate, Time and Principal

 Required amount can be calculated.

 Both the statements I and II together are sufficient.

Considering statements II and III together

r = 5%

S.I. = 6P

∵ The principal can not be calculated

∴ Both II and III together are not sufficient to answer the question.

Considering statements I and III together

S.I. = 6P

⇒ PRT/100 = 6P

⇒ 3R/100 = 6

⇒ R = 200%

S.I. = PRT/100

800 = P × 200 × 5/100

P = 80

∵ We have Principal, Rate and Time

 Required amount can be calculated.

∴ Both I and III together are also not sufficient to answer the question

⇒ Statement I and either statement II or statement III together are sufficient to answer the question.

Related Questions

The following question have three statements. Study the question and the statements and decide which of the statement(s) is/are necessary to answer the question. Suman borrowed some amount of money at compound interest for 3 years. Find the amount to be paid by her after 3 years. Statement I: Simple interest on the same sum at the same rate of interest in 5 years will be 1/4th of the principal. Statement II: The simple interest on the sum after 6 years will be Rs. 12000. Statement III: The sum borrowed is 5 times the simple interest of 4 years.