Question

If $A:B=3:4$ and $B:C=8:9$, then find $A:C$.

Answer 1

We have,

$A:B=3:4$

$\frac{A}{B}=\frac{3}{4}......\left(1\right)$

On multiplying by 8 in equation ( 1)

$\frac{A}{B}=\frac{3\times 8}{4\times 8}=\frac{24}{32}$ …… ( 2)

So,

$\frac{B}{C}=\frac{8}{9}......\left(3\right)$

On multiplying by 4 in equation ( 3)

$\frac{B}{C}=\frac{8\times 4}{9\times 4}=\frac{32}{36}......\left(4\right)$

From equation ( 2) and ( 4) to, and we get,

$\frac{A}{C}=\frac{24}{36}=\frac{2}{3}$

$A:C=2:3$

Hence, this is the answer.