Question

em 8.
If amount of 50,000 becomes 65,000 in 3 years, the rate of simple interest
must be
(a) 8%
D 10%
(c) 12%
(d) None of these​

Answer 1

Given :-

• Principal ( P ) = Rs 50,000
• Amount ( A ) = Rs 65,000  
• Time ( T ) = 3 years

To Find :-

• Find the rate ( r ) of simple interest ( SI )

Solution :-

~Here, we’re given the principal , amount, time and we need to find the rate of simple interest. Firstly , we’ll find the simple interest by subtracting the principal from amount and then  we can  easily find the rate of simple interest by putting the values in the formula of simple interest.

_____________

As we know that ,

★ SI = P × r × T/100

Where,

• SI is Simple Interest
• P is principal
• T is time
• r is rate of interest  

★ SI = Amount – Principal

_____________

Finding the Simple interest :-

$\sf \dashrightarrow Rs \; 65,000 - Rs \; 50,000$

$\boxed{\bf{ \bigstar \;\; Rs \; 15,000 }}$

Finding the rate of simple interest :-

$\sf \dashrightarrow 15,000 = \dfrac{ 50,000 \times 3 \times r }{100}$

$\sf \dashrightarrow 15,000 = 500 \times 3 \times r$

$\sf \dashrightarrow 15,000 = 15,000 \times r$

$\sf \dashrightarrow r = \dfrac{15,000}{15,000}$

$\boxed{\bf{ \bigstar \;\; Rate = 1 \% }}$

_____________

Hence,  

• The rate of simple interest is 1 %