Money lent to A+B = (300+ 540) = Rs. 840

Amount received = Rs. 1032

Interest received = Rs. 1032 - Rs.840 = Rs. 192

Interest on Rs. 300 lent to A for 1 year = = Rs. 12

Interest on Rs.540 lent to B for 1 year = = Rs. 36

Total yearly interest = Rs.(12+36)

= Rs.48

If interest is Rs. 48, time = 1 year

if interest is Rs. 192, time =

= 4 years

A) 7.85 % | B) 9.41% |

C) 6.66 % | D) 4.21 % |

Explanation:

Let the principle be Rs. P

As the amount double itself the interest is Rs. P too

So P = P x r x 15/100

=> r = 100/15 = 20/3 % = 6.66 %.

A) Rs. 1800 | B) Rs. 2000 |

C) Rs. 1400 | D) Rs. 1250 |

Explanation:

2500 in 5th year and 3000 in 7th year

So in between 2 years Rs. 500 is increased => for a year 500/2 = 250

So, per year it is increasing Rs.250 then in 5 years => 250 x 5 = 1250

Hence, the initial amount must be 2500 - 1250 = Rs. 1250

A) 13.33 % | B) 14.25 % |

C) 16.98 % | D) 18.75 % |

Explanation:

Given,

S.I = 3 Principal Amount

=> 3A = A x 16 x R/100

By solving, we get

=> R = 18.75%

A) Rs. 540 | B) Rs. 415 |

C) Rs. 404 | D) Data is not sufficient |

Explanation:

Let the sum be Rs. p, rate be R% p.a. and time be T years.

Then,

And,

Clearly, from (1) and (2), we cannot find the value of p

So, the data is not sufficient.

A) Only a is sufficient | B) Neither a nor b is sufficient |

C) Only b is sufficient | D) Both a and b sufficient |

Explanation:

Let the sum be Rs. x

a. gives, S.I = Rs. 9000 and time = 9 years.

b. gives, Sum + S.I for 6 years = 2 x Sum

Sum = S.I for 6 years.

Now, S.I for 9 years = Rs. 9000

S.I for 1 year = Rs. 9000/9 = Rs. 1000.

S.I for 6 years = Rs. (1000 x 6)= Rs. 6000.

x = Rs. 6000

Thus, both a and b are necessary to answer the question.