Question

Olivia bought $40$ m wire for fencing her own rectangular field of length $9$ m and width $7$ m. How much wire is left with her?

• A. $4$ m
• B. $8$ m
• C. $12$ m
• D. $14$ m

Answer 1

The correct option is B $8$ m

Wire required to fence the field
= Perimeter of the field
$=2\times$(Length + Width)
(Perimeter of rectangle = $2\times$ (Length + Width))
$=2\times (9+7)$
$=2\times 16$
$=32$ m

Wire left = Total wire - Wire used
$=40-32=8$ m

Therefore, wire left with Olivia = $8$ m, (b) is the correct option.