Question

Forty-two percent of what number is 168?

Answer 1

$42\%\ of\ x\ is\ 168\\\\42\%=\dfrac{42}{100}=0.42\\\\42\%\ of\ x\to0.42x\\\\the\ equation:\\\\0.42x=168\ \ \ |divide\ both\ sides\ by\ 0.42\\\\\boxed{x = 400}$