Awoman earns $2700 per month and budgets $351 per month on food. what percent of her income is spent on food?

($351/$2700) x 100 

What you are basically doing with this is that you are finding the decimal value of the quotient and then since you need to find the percent you would have to multiply the decimal value by 100. 

0.13 x 100 = 13% <- (answer)