Question

if 16% of A=20% of B then A:B is

Answer 1

$\frac{16}{100} \times a = \frac{20}{100} \times b$
This is given.
Therefore,
$\frac{a}{b} = \frac{20}{100} \times \frac{100}{16}$
So,
$\frac{a}{b} = \frac{20}{16}$
or
$\frac{a}{b} = \frac{5}{4}$

Answer 2

16 by 100×A=20 by 100
a by b=20 by 100 ×100 by 16
a by b=20 by 16
a by b=5 by 4
so a:b=5:4