If you would like to know the amount they spend on rent each year you would take 15% of $45,000 or .15 x 45,000 = $6,750
You could also do it mentally 10% of 45,000 is 4500 plus
5% of 45,000 is 2250 (1/2 of 10% or 1/2 of 4500)
Together they add up to $6750