Answer:
Total amount she spent on the posters = $43.2 + $10.8 = $54
Explanation:
Lila bought a green poster that measured 36 inches by 24 inches and a red poster that measured 12 inches by 18 inches. The posters cost per square inch is $0.05 .
To know how much she spend on the posters one have to convert the measured values of the posters to square inches(area).
Green poster
area of rectangle = Lb
area of rectangle = 36 × 24
area of rectangle = 864 square inch
since 1 square inch = $0.05
864 square inch = ?
cross multiply
864 × 0.05 = $43.2
Red posters
area of rectangle = Lb
area of rectangle = 12 × 18
area of rectangle = 216 square inches
since 1 square inch = $0.05
864 square inch = ?
cross multiply
216 × 0.05 = $10.8
Total amount she spent on the posters = $43.2 + $10.8 = $54