Question

A well of diameter 150 cm has a stone parapet around it. If the length of the outer edge of the
parapet is 660 cm, then find the width of the parapet.

Answer 1

Answer :

• Width of the parapet is 30cm

Given :

• Diameter is 150cm
• Length of the outer edge of the parapet is 660cm

To find :

• The width of parapet

Solution :

Diamter is 150cm

Radius = 150/2 = 75cm

• Let the width of parapet be x

Then Radius = (75 + x)

As we know that,

• Circumference = 2πr

》 2 × 22/7 × (75 + x)

》44/7 × (75 + x)

According To Question Given that,

• Outer edge of the parapet is 660cm so ,

》 44/7 × (75 + x) = 660

》 75 + x = 600 × 7 / 44

》105

Now we have to find the width of the parapet

• outer radius - inner radius

》105 - 75

》30cm

Hence , Width of the parapet is 30cm