67. Rs. 800 becomes Rs. 956 in 3 years at a certain rate of simple int

1.	67. Rs. 800 becomes Rs. 956 in 3 years at a certain rate of simple interest.If the rate of interest is increased by 4% what amount will Rs. 800become in 3 years?(a) Rs. 1020.80(b) Rs. 1025(c) Rs. 1052(d) Rs. 1050
Answer» We know that formulae: SI = P× R × T /100 We have Principal P = 800 T = 3 years ⇒ SI = Amount – P ⇒ SI = 956 – 800 = 156 Hence, ⇒ 156 = 800 × R × 3/100 ⇒156 = 24R ⇒ R = 156/24 Hence we have R = 6.5 % p.a. Now, we have the rate of interest increased by 4% Hence, new rate of interest as 6.5 + 4 = 10% p.a. New SI = 800 × 10.5 × 3/100 ⇒ SI = 252 Amount after 3 years at new Rate of interest = P + SI = 800 + 252 = 1052

67. Rs. 800 becomes Rs. 956 in 3 years at a certain rate of simple interest.If the rate of interest is increased by 4% what amount will Rs. 800become in 3 years?(a) Rs. 1020.80(b) Rs. 1025(c) Rs. 1052(d) Rs. 1050

Answer»

We know that formulae:

SI = P× R × T /100

We have Principal P = 800

T = 3 years

⇒ SI = Amount – P

⇒ SI = 956 – 800 = 156

Hence,

⇒ 156 = 800 × R × 3/100

⇒156 = 24R

⇒ R = 156/24

Hence we have

R = 6.5 % p.a.

Now, we have the rate of interest increased by 4%

Hence, new rate of interest as 6.5 + 4 = 10% p.a.

New SI = 800 × 10.5 × 3/100

⇒ SI = 252

Amount after 3 years at new Rate of interest = P + SI = 800 + 252

= 1052