ad

6. A person borrows $₹5000$ for $2$ years at $4\%$ per annum simple interest. He immediately lends it to another person at $6\dfrac{1}{4}\%$ per annum for $2$ years. Find his gain in the transaction per year. | |

A. $₹112.50$ | B. $₹167.50$ |

C. $₹225$ | D. $₹150$ |

Discuss |

answer with explanation

Answer: Option A

Explanation:

Difference in interest rate

$=6\dfrac{1}{4}\%-4\%=2\dfrac{1}{4}\%=\dfrac{9}{4}\%$

Gain per year

= simple interest on $5000$ at $\dfrac{9}{4}\%$ for $1$ year

$=\dfrac{5000×\dfrac{9}{4}×1}{100}=112.5$

Simple interest he pays

$=\dfrac{5000×4×2}{100}=400$

Simple interest he gets

$=\dfrac{5000×\dfrac{25}{4}×2}{100}=625$

Gain in $2$ years $= 625-400=225$

Gain per year $=\dfrac{225}{2}=112.5$

7. What is the ratio of simple interest earned by a certain amount at the same rate of interest for $5$ years and that for $15$ years? | |

A. $3:1$ | B. $1:3$ |

C. $3:2$ | D. $2:3$ |

Discuss |

answer with explanation

Answer: Option B

Explanation:

Required ratio

$=\dfrac{\text{PR}×5}{100}:\dfrac{\text{PR}×15}{100}\\=5:15=1:3$

Simple interest $=\dfrac{\text{PRT}}{100}.$ In this case, P and R are constants and therefore simple interest $\propto \text{T}$

Therefore, required ratio

$=\text{T}_1:\text{T}_2=5:15=1:3$

8. A sum of money amounts to $₹9800$ after $5$ years and $₹12005$ after $8$ years at the same rate of simple interest. The rate of interest per annum is | |

A. $15\%$ | B. $5\%$ |

C. $12\%$ | D. $8\%$ |

Discuss |

answer with explanation

Answer: Option C

Explanation:

Simple interest for $3$ years

$=12005-9800=2205$

Simple interest for $5$ years

$=\dfrac{2205}{3}×5=3675$

Sum of money $=9800-3675=6125$

$\text{R}=\dfrac{100×2205}{6125×3}=12$

9. A certain amount earns simple interest of $₹1200$ after $10$ years. Had the interest been $2\%$ more, how much more interest would it have earned? | |

A. None of these | B. $₹120$ |

C. Cannot be determined | D. $₹25$ |

Discuss |

answer with explanation

Answer: Option C

Explanation:

Required details cannot be found out with the given information.10. A man took loan from a bank at the rate of $8\%$ per annum simple interest. After $4$ years he had to pay $₹6200$ interest only for the period. What was the principal amount borrowed by him? | |

A. $₹20245$ | B. $₹18230$ |

C. $₹17322$ | D. $₹19375$ |

Discuss |

answer with explanation

Answer: Option D

Explanation:

$\text{P}=\dfrac{100×\text{SI}}{\text{RT}}=\dfrac{100×6200}{8×4}=19375$preview