Patrick got a change of $14.90 for paying for the material with a $20 bill.
Explanation:
1 yard of material costs $3.40. Patrick bought 54 inches of material. First, we must convert the inches into yards. We have 36 inches = 1 yard. To calculate how many yards 54 inches we divide the 54 by the 36. So 54 inches of material = 54 / 36 yards = 1.5 yards of material
Since 1 yard of material costs $3.40, the cost of 1.5 yards of material = 1.5 × $3.40 = $5.10. Patrick paid for the material with a $20 bill. So the change Patrick got = $20 - $5.10 = $14.90.
