10th Class Mathematics Areas Related to Circles Question Bank MCQs - Areas Related to Circles

If the difference between the circumference and the radius of a circle is \[\text{37 cm},\] then using \[\pi =\frac{22}{7}\] the circumference (in cm) of the circle is: (CBSE 2013)

A) 154

B) 44

C) 14

D) 7

Correct Answer: B

Solution :

[b] A.T.Q.

\[2\pi r-r=37\]

\[\Rightarrow \,\,\,\,\,\,\,\,\,\,\,\,2\times \frac{22}{7}r-r=37\]

\[\frac{37}{7}r=37\,\,\,\,\,\,\,\,\,\Rightarrow \,\,\,\,\,\,r=7\]

\[\therefore \] Circumference \[=2\times \frac{22}{7}\times 7=44\]