#### Question

Find the amount and the compound interest.

No. | Principal (₹) | Rate (p.c.p.a.) | Duration (Years) |

1 | 2000 | 5 | 2 |

2 | 5000 | 8 | 3 |

3 | 4000 | 7.5 | 2 |

#### Solution

(1) Here, P = ₹ 2000; R = 5 % ; N = 2 years

A = P `( 1 + "R"/100)^"N"`

= 2000 `(1 + 5/100)² `

= 2000 `(21/20)²`

= 2205 Rupees

Compound interest after 2 years,

I = Amount - Principal

= 2205 - 2000

= 205 Rupees

Hence, Amount = ₹ 2205 and compound interest = ₹205.

(2) Here, P = ₹ 5000; R = 8 % ; N = 3 years

A = P `( 1 + "R"/100)^"N"`

= 5000 `(1 + 8/100)³`

= 5000 `(108/100)²`

= 5000 `(27/25)³`

= 6298.56 Rupees

Compound interest after 3 years,

I = Amount - Principal

= 6298.56- 5000

= 1298.56 Rupees

Hence, Amount = ₹ 6298.56 and compound interest = ₹1298.56.

(3) Here, P = ₹ 4000; R = 7.5 % ; N = 2 years

A = P `( 1 + "R"/100)^"N"`

= 4000 `(1 + 7.5/100)²`

= 4000 `(1 +75/1000)²`

= 4000 `(1000/1075)²`

= 4000 `(43/40)²`

= 4622.50 Rupees

Compound interest after 2 years,

I = Amount - Principal

= 4622.50 - 4000

= 622.50 Rupees

Hence, Amount = ₹ 4622.50 and compound interest = ₹ 622.50.