SAT Question 41b71b4e: Percentages answer and explanation with Desmos solution

Choice B is correct. The decimal equivalent of $20\%$ is $0.2$. The number that is $20\%$ greater than $60$ is also $120\%$ of $60$. The decimal equivalent of $120\%$ is $1.2$, and $1.2\times 60=72$.

Alternate approach: $10\%$ of $60$ is $6$, and $20\%$ of $60$ is double that amount, or $12$. It follows that the number that is $20\%$ greater than $60$ is $12$ more than $60$, or $60+12=72$.