0.80m
0.50c
1.40B
0.50(8)+0.80(16)
1.40(5)-12.8(3)
31.04 should be your answer, sorry if I'm wrong!
The area of the scale drawing would be 1080 square centimeters or (1080 cm^2). I got this answer through first finding the area of the classroom in feet (which is A= lw = [18][20] = 360 ft^2) and then I proceeded to converting it to centimeters via given scale factor (3 cm = 1 foot) and had the answer of 1080 centimeters squared.
Length + width = 1/2 the perimeter:30/2 = 15
Area = length x width
List the factors of 50: 1, 2, 5, 10, 25, 50.
Find the two factors that when added together equal 15:
Dimensions are 5 cm by 10 cm.