Question

solve the proportion: 20/16 = x/80 question 19 options: 6.25 1600 100 160

Answer 1

$\dfrac{20}{16}=\dfrac{20:4}{16:4}=\dfrac{5}{4}\\\\\dfrac{5}{4}=\dfrac{x}{80}\ \ \ \ |cross\ multiply\\\\4x=5\cdot80\\\\4x=400\ \  \ \ |divide\ both\ sides\ by\ 4\\\\\boxed{x=100}$