area=length x width
A=lw
A=12 3/8
l=x
w=2 3/4
first, make your mixed numbers into improper fractions
12 3/8 --> 99/8
2 3/4 --> 11/4
then, set equal denominators
99/8 and 22/8
99/8=22/8x --plug in values
99/22=x --divide both sides by 22/8
convert improper fraction to mixed number
99/22 --> 4 11/22 --> 4 1/2
therefore, the length is 4 1/2 meters
