Question

4. A rhombus shaped sheet with perimeter 40 cm
and one diagonal 12 cm, is painted on both sides
at the rate of Rs. 5 per m². Find the cost of
painting​

Answer 1

Step-by-step explanation:

• given d1 = 12 m

perimeter of rhombus = 40

4a = 40

a = 40/4

a = 10m

• Now find d2

d2 = [ 4a^2 - d1^2] ^1/2

d2 = [ 4(10)^2 - (12)^2] ^1/2

d2 = [ 400 - 144 ]^1/2

d2 = [ 256 ]^1/2

d2 = 16 m

• Now find area

Area of rhombus = (d1×d2)/2

= (12×16)/2

= 96 m^2

• Two sides area = 2×96

= 192 m^2

• Now find cost of painting

rate per m^2 = 5

rate for 192m^2 = 192×5

= 960