Question

Answer 1

\(\dfrac{12}{16}=\dfrac{a}{20}\\ =>a=\dfrac{12.20}{16}=15\\ \dfrac{12}{16}=\dfrac{9}{b}\\ =>b=\dfrac{16.9}{12}=12\)

Answer 2

`a = 12 xx 20 : 16 = 15`

`b = 20 xx 9 : 15 = 12`

Answer 3

\(\dfrac{12}{16}=\dfrac{a}{20}=\dfrac{9}{b}=\dfrac{3}{4}=\dfrac{a}{4}=\dfrac{3}{b}\) (rút gọn)

\(=>\dfrac{a}{4}=\dfrac{3}{4}=\dfrac{15}{20},\dfrac{3}{b}=\dfrac{3}{4}=\dfrac{9}{12}\)

\(=>a=15,b=12\)