Question

In a school out of 300 students, 70% are girls and 30% are boys. If 30 girls leave And no new boy admitted what is the new percentage of girls in the school

Answer 1

Number of children in a school $$= 300$$

Number of a boys $$= 30 \% \ of\ 300 $$

we can write it as

$$ \dfrac{30}{100} \times 300 $$

$$= 90$$

Number of girls in the school$$= 70 \% \ of\ 300$$

We can write it as

$$ \dfrac{70}{100} \times 300 $$

$$= 210 $$

Number of girls left $$ = 30$$

Number of girls still in the school$$=210-30=180$$

Total number of student $$=180+90=270$$

$$percentage\ of\ girls=\dfrac{180}{270}\times 100$$

$$=\dfrac{200}{3}=66\dfrac23\%$$