Chapter 4 - Proportions, Percents, and Solving Inequalities - 4.2 - Percents and Problem Solving - Problem Set 4.2 - Page 155: 27

The number we are looking for is 350.

Let X represent the number we are looking for. 1.2% of what number means 1.2% $\times$ X So, this question translates to: 1.2% $\times$ X = 4.2 0.012 $\times$ X = 4.2 Divide both sides by 0.012 X = 350