Question

the perimeter of rectangle is 13cm and it's width is three 2/4 cm find its length

Answer 1

perimetre=13 cm

perimetre of a rectangle=2(l+b)

breadth=3 2/4

breadth=14/4

=7/2

∴13=2(l+7/2)

2l+2×7/2=13

2l+7=13

2l=13-7

2l=6

l=6/2

l=3

Answer 2

given perimeter =13
perimeter of rectangle = 2(l+b)
width= breadth = 3 2/4
breadth =14/4= 7/2
substitute in formula
13= 2(l + 7/2
2l + 2×7/2 =13
2l +7=13
2l= 13-7
2l=6
l =6/2
l=3
length=3cm