A sum of money kept in a hank amounts to Rs. 600/– in 4 years and Rs

1.	A sum of money kept in a hank amounts to Rs. 600/– in 4 years and Rs. 800/– in 12 years. Find the sum and interest carried every year.
Answer» Let the required sum = a and the interest carried every year = d According to question, In 4years, a sum of money kept in bank account = Rs. 600 i.e. t₅ = 600 ⇒ a + 4d = 600 …(i) and in 12 years , sum of money kept = Rs. 800 i.e. t₁₃ = 800 ⇒ a + 12d = 800 …(ii) Solving linear equations (i) and (ii), we get a + 4d – a – 12d = 600 – 800 ⇒ – 8d = –200 ⇒ d = 25 Putting the value of d in eq.(i), we get a + 4(25) = 600 ⇒ a + 100 = 600 ⇒ a = 500 Hence, the sum and interest carried every year is Rs 500 and Rs 25 respectively.

A sum of money kept in a hank amounts to Rs. 600/– in 4 years and Rs. 800/– in 12 years. Find the sum and interest carried every year.

Answer»

Let the required sum = a

and the interest carried every year = d

According to question,

In 4years, a sum of money kept in bank account = Rs. 600

i.e. t₅ = 600 ⇒ a + 4d = 600 …(i)

and in 12 years , sum of money kept = Rs. 800

i.e. t₁₃ = 800 ⇒ a + 12d = 800 …(ii)

Solving linear equations (i) and (ii), we get

a + 4d – a – 12d = 600 – 800

⇒ – 8d = –200

⇒ d = 25

Putting the value of d in eq.(i), we get

a + 4(25) = 600

⇒ a + 100 = 600

⇒ a = 500

Hence, the sum and interest carried every year is Rs 500 and Rs 25 respectively.