Question

13. Find the principal if the interest compounded at the
rate of 10% per annum for two years is ₹420..
d
e
(a) ₹2000
(c) ₹1000
(b) ₹ 2200
(d) ₹ 1100​

Answer 1

☯ Given,

• Rate of interest (R) = 10%
• Time (t) = 2 years
• Compound interest (C.I) = Rs. 420

☯ To Find,

• Principal, P

☯ Solution,

As we know that,

C.I = P(1 + R/100)^t - P

=> 420 = P(1 + 10/100)² - P

=> 420 = P(100 + 10/100)² - P

=> 420 = P(110/100)² - P

=> 420 = P(11/10)² - P

=> 420 = 121/100P - P

=> 420 = 121P - 100P/100

=> 420 = 21P/100

=> 42000 = 21P

=> P = 42000/21

=> P = Rs. 2000

☯ Hence,

Principal is equal to Rs. 2000.

Answer 2

$\Huge\tt{{\color{navy}{{\underline{AN}}}}{\color{blue}{{\underline{SW}}}}{\blue{{\underline{ER}}}}{\color{skyblue}{:}}}$

$\huge\color{navy}{\textbf{\textsf{GIVEN :-}}}$

• Rate of Interest (R) = 10%
• Time (t) = 2 years
• Compound Interest (C.I) = Rs. 420

$\huge\color{blue}{\textbf{\textsf{TO FIND :-}}}$

• Principal (P)

$\huge\color{skyblue}{\textbf{\textsf{SOLUTION :-}}}$

C.I = P(1 + R/100)^t - P

→ 420 = P(1 + 10/100)² - P

→ 420 = P(100 + 10/100)² - P

→ 420 = P(110/100)² - P

→ 420 = P(11/10)² - P

→ 420 = 121/100P - P

→ 420 = 121P - 100P/100

→ 420 = 21P/100

→ 42000 = 21P

→ P = 42000/21

→ P = Rs. 2000

Hence, the principal is Rs. 2000.

Hope it Helps Buddy ♥️