## Chapter 14 – Banks and Simple Interest

## Practice Set 35

**(1) At a rate of 10 p.c.p.a., what would be the interest for one year on ₹ 6000?**

**Solution: **

Principal = Rs 6000

Rate of Interest = 10 p.c.p.a.

Let interest on principal Rs 6000 be Rs x.

The ratio of principal to interest is,

\(\large \frac {x}{6000}\) = \(\large \frac {10}{100}\)

∴ \(\large \frac {x}{6000}\) × 6000 = \(\large \frac {10}{100}\) × 6000 …(Multiplying both sides by 6000).

∴ x = 10 × 60

∴ x = 600

**Ans:** The interest for one year is Rs 600.

**(2) Mahesh deposited ₹ 8650 in a bank at a rate of 6 p.c.p.a. How much money will he get at the end of the year in all?**

**Solution: **

Principal = Rs 8650

Rate of interest = 6 p.c.p.a.

Let the interest on principal Rs 8650 be Rs x.

The ratio of principal to interest is,

\(\large \frac {x}{8650}\) = \(\large \frac {6}{100}\)

∴ \(\large \frac {x}{8650}\) × 8650 = \(\large \frac {6}{100}\) × 8650 …(Multiplying both sides by 8650)

∴ x = \(\large \frac {6\,×\,8650}{100}\)

∴ x = 519

∴ Amount received at the end of the year

= Principal + Interest

= Rs 8650 + Rs 519

= Rs 9169

**Ans:** Mahesh will get Rs 9169 at the end of the year.

**(3) Ahmed Chacha borrowed ₹ 25000 at 12 p.c.p.a. for a year. What amount will he have to return to the bank at the end of the year?**

**Solution: **

Principal: = Rs 25,000

Rate of interest = 12 p.c.p.a.

Let interest on principal Rs 25,000 be Rs x.

The ratio of principal to interest is,

\(\large \frac {x}{25000}\) = \(\large \frac {12}{100}\)

∴ \(\large \frac {x}{25000}\) × 25000 = \(\large \frac {12}{100}\) × 25000 …(Multiplying both sides by 25000)

∴ x = \(\large \frac {12\,×\,25000}{100}\)

∴ x = 3000

Amount to be returned to the bank at the end of the year

= Principal + Interest

= Rs 25,000 + Rs 3,000

= Rs 28,000

**Ans:** Ahmad Chacha has to return Rs 28,000 to the bank at the end of the year.

**(4) Kisanrao wanted to make a pond in his field. He borrowed ₹ 35250 from a bank at an interest rate of 6 p.c.p.a. How much interest will he have to pay to the bank at the end of the year?**

**Solution: **

Principal = Rs 35,250

Rate of interest = 6 p.c.p.a.

Let interest on principal Rs 35,250 be Rs x.

The ratio of principal to interest is,

\(\large \frac {x}{35250}\) = \(\large \frac {6}{100}\)

∴ \(\large \frac {x}{35250}\) × 35250 = \(\large \frac {6}{100}\) × 35250 …(Multiplying both sides by 35250)

∴ x = \(\large \frac {6\,×\,35250}{100}\)

∴ x = 2115

**Ans:** Kisanrao will have to pay an interest of Rs 2115 to the bank at the end of the year.