Question

Saurabh invests Rs48,000 for 7 years at 10% per annum compound interest.

Calculate:

(i)the interest for the first year.

(ii)the amount at the end of second year.

(iii) the interest for the third year.​

Answer 1

Answer:

Saurabh invests Rs48,000 for 7 years at 10% per annum

(i)the interest for the first year.

= 10 % of 48000

= 48000 x 10%

= 48000 x 10/100

= 48000 x 0.1

= 4800

(ii)the amount at the end of second year.

first year total ₹ = 48000 + 10 % of 48000

= 48000 + 48000 x 10%

= 48000 + 48000 x 10/100

= 48000 + 48000 x 0.1

= 48000 + 4800

= 52,800

so secound year is = 1 year x 2

= 1,05,600/-

(iii) the interest for the third year.

the interest for the third year = 3 x 1 year

= 3 x 4800

= 14, 400.

Answer 2

Question:

Saurabh invests Rs48,000 for 7 years at 10% per annum compound interest.

Calculate:

(i)the interest for the first year.

(ii)the amount at the end of second year.

(iii) the interest for the third year.

Here:

• P refers to ➞ Principal
• R refers to ➞Interest rate
• T refers to ➞ Time period
• Interest 1 refers to ➞ Interest of 1 year
• Amount 1 refers to ➞ Amount of 1 year
• Interest 2 refers to ➞ Interest of 2 year
• Amount 2 refers to ➞ Amount of 2 year
• Interest 3 refers to ➞ Interest of 3 year

Answer:

Part 1:

To find value of Interest for the first year.

$\bold{Interest \:1= \dfrac{P \times R \times T}{100}}$

$\bold{Interest \:1= \dfrac{₹48000 \times 10 \times 1}{100}}$

$\red{\bold{Interest \:1=₹4800}}$

Part 2:

To find the amount at the end of second year first we have to find Amount after first year and then Interest of 2 year

$\bold{Amount\:1=Interest\:1+P}$

$\bold{Amount\:1=₹4800+₹48000}$

$\bold{Amount\:1=₹52800}$

Now let's find interest of 2 year

$\bold{Interest \:2= \dfrac{Amount\:1 \times R \times T}{100}}$

$\bold{Interest \:2= \dfrac{52800\times 10 \times 1}{100}}$

$\bold{Interest \:2= 5280}$

Now finally we can find Amount at the end of 2 year

$\bold{Amount\:2=Interest\:2+Amount\:1}$

$\bold{Amount\:2=5280+52800}$

$\red{\bold{Amount\:2=₹58080 }}$

Part 3:

To find interest of 3 year:

$\bold{Interest \:3= \dfrac{Amount\:2 \times R \times T}{100}}$

$\bold{Interest \:3= \dfrac{ ₹58080\times 10 \times 1}{100}}$

$\red{\bold{Interest \:3=₹5808 } }$

hope it helps!