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.