How do I answer this ttpe of question?

You would want to use this helpful formula: [tex]\frac{is}{of}[/tex] = [tex]\frac{percent}{100}[/tex]
The $69.50 would be the of and the 45% would be the percent. Plugging in gives you,
[tex]\frac{x}{69.50}[/tex] = [tex]\frac{45}{100}[/tex]
You then cross multiply giving you,
3127.5 = 100x
You then divide both sides by 100 giving you,
31.275 = 100
Since it is money you would round to the hundredths place giving you the final answer of,
B. $31.28