A sum of rs. 3000 amounts to rs. 6000 in two years at compound interest. The interest for four years is?
Answers
Answered by
1
Answer:Principal=Rs. 3000.
Amount=Rs. 6000.
Time=2 years.
A=P(1+(r/100))^2.
=> 6000=3000(1+(r/100))^2.
=> ((100+r)/100)^2=2.
=> (100+r)×(100+r)=20000.
=> 100r+100r+r²+10000=20000.
=> r²+200r-10000=0.
=> (r-100)(r+100)
Taking the positive outcome, r=100.
Therefore, putting the values the amount after 4 years will be Rs. 9000.
So, interest = Amount - Principal.
Therefore, interest = 9000-3000.
Interest for 4 years = Rs. 6000.
Explanation: Rs. 3000 result to 6000 after 2 years. So the interest should be Rs. 3000 in 2 years. After solving, we get the rate. And after substituting it's value in the formula with t = 4 years. We get the interest for four years equal to Rs. 6000.
Similar questions