Question

the area of the rectangle is 650cm2 and its width is 13cm. find the perimeter of the rectangle. also, calculate its area if the length is 15% more than its width

Answer 1

Find the length:

Area = Length x Width

Given area = 650 cm² and width = 13 cm

650 = 13 x Length

Length = 650 ÷ 13 = 50 cm

Find the perimeter:

Perimeter = 2 (Length + Width)

Perimeter = 2( 50 + 13) = 126 cm

Find the new length:

15% of the width = 0.15 x 13 = 1.95

New length = 13 + 1.95 = 14.95 cm

Find the new area:

Area = Length x width

Area = 14.95 x 13 = 194.35 cm²

Answer: The perimeter is 126 cm. The new area is 194.35 cm²

Answer 2

here is your answer OK dude


Let the breadth=x
    the length  =x+15
given perimeter= 150
we know 
Perimeter of rectangle = 2(l+b)
                          150 = 2( x+ x+15)
                           75 = 2x +15
                            60 = 2x
                             30=x 
therefore breadth = 30 cm 
              length   = 30 +15  = 45 cm

check 
150 = 2( 45+30)
150 = 2(75)
150 = 150 
LHS=RHS
hence prooved