Answer:
width = 5.5 cm
Step-by-step explanation:
The perimeter (P) of a rectangle is calculated as
P = 2l + 2w ( l is the length and w the width )
Here P = 91 and l = 40 , thus
91 = 2(40) + 2w = 80 + 2w ( subtract 80 from both sides )
11 = 2w ( divide both sides by 2 )
5.5 = w
Thus width is 5.5 cm
