Question

If

a.b = 2:3 and

b.c = 4: 5 then what is

a.b:c ?

Answer 1

$\frac{a}{b} = \frac{2}{3} = \frac{2 \times 4}{3 \times 4} = \frac{8}{12} \\ \\ \frac{b}{c} = \frac{4}{5} = \frac{4 \times 3}{5 \times 3} = \frac{12}{15}$
therefore

a : b : c = 8 : 12 : 15