estimate: 20 is 22% of what number?\na 40\nb 50\nc 75\nd 100

Explanation:

Step1: Set up the equation

Let the number be $x$. We know that $22%$ of $x$ is $20$, so $0.22x = 20$.

Step2: Solve for $x$

$x=\frac{20}{0.22}\approx\frac{20}{0.2}=100$.

Answer:

D. 100