Question

A sum of money amounts 10000 after 5 years and 15000 after 8 years at the same rate of simple interest. Find the rate of interest per annum .

Answer 1

main balance of 8 yrs+interest=15000

main balance of 5 yrs+interest=10000

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(-)main balance of 3 yrs= 5000

then main balance of 5 years=5000×5/3

then,main balance (p)=5000×5

rate of interest (r)=s%

time (t)=5 yrs

interest =5000×5/3×s×5/100=1250s/3

then,5000+1250s/3=10000

or,1250s/3=5000

or,s=5000/1250×3=4×3=12

the rate of interest is 12%

Answer 2

Answer:

Step-by-step explanation: