A certain sum amounts to Rs. 756 in 2 years and to Rs. 873 in 3.5 years at a certain rate of simple interest. Find the rate of interest per annum.
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 13%
Amount after 2 years = 756 ---- (1)
Amount after 3.5 years = 873 ---- (2)
Subtracting (2) from (1)
⇒ Interest in 1.5 years = 117
⇒ Interest in 2 years = 117 × (2/1.5)
⇒ Rs.156
Amount after 2 years = 756 = Principal + Interest
⇒ 756 = Principal + 156
⇒ Principal = Rs. 600
⇒ 156 = (600 × r × 2)/100
⇒ r = 13%