Question

the strenth of a school increased by 10%during one year and then by 20% during the next year the total no.of students then became 528find the original strength of the school

Answer 1

Let original strength be 'x'.
Let R1 = First growth rate =10%
Let R2=Second growth rate=20%
Final population=528
x(1+R1/100)(1+R2/100)=528
x(1+0.1)(1+0.2)=528
x(1.1)(1/2)=528
x=528/1.32
x=400
Thus, the initial population was 400