At what rate percent compound interest does a sum of money becomes 4 times of itself in 4 years?

2.

The time, in which Rs.2,000 will amount to Rs. 2,420 at 10% per annum compound interest, when the interest is compounded annually is,

• 5 years

• 2 years

• 3 years

• 3 years

B.

2 years

Shortcut Method:Go with option, 

The RRB Group D Results are expected to be out soon! The Railway Recruitment Board released the RRB Group D Answer Key on 14th October 2022. The candidates will be able to raise objections from 15th to 19th October 2022. The exam was conducted from 17th August to 11th October 2022. The RRB (Railway Recruitment Board) is conducting the RRB Group D exam to recruit various posts of Track Maintainer, Helper/Assistant in various technical departments like Electrical, Mechanical, S&T, etc. The selection process for these posts includes 4 phases- Computer Based Test Physical Efficiency Test, Document Verification, and Medical Test.