Question

If Rs. 1100 is obtained after lending out Rs. x at 5% per annum for 2 years and Rs. 1800 is obtained after lending out Rs. y at 10% per annum for 2 years, find x + y.​

Answer 1

simple interest

Amount =1100 rs

time(t) = 2 year

rate p.a (r)= 5%

we know that

$principal = \frac{100}{100 + (rt)} \times amount \\ \frac{100}{100 + 10} \times 1100 \\ \frac{100}{110} \times 1100 \\ x = 1000$

Amount =1800 rs

time(t) = 2 year

rate p.a (r)= 10%

we know that

$principal = \frac{100}{100 + (rt)} \times amount \\ \frac{100}{100 + 20} \times 1800 \\ \frac{100}{120} \times 1800 \\ \frac{100}{20} \times 300\\ y = 1500$

x+y=1000+1500=2500