Explanation
Let us solve this problem step-by-step using standard algebraic formulas for a circle.
Step 1: Set up the equation using given conditions
Let the radius of the circle be r cm.
The formulas related to a circle are:
Circumference=2πr
Area=πr2
According to the question, the difference between the circumference and the radius is 37 cm. We can express this as:
2πr−r=37
Step 2: Solve for the radius (r)
Factor out the common term r from the left side of the equation:
r(2π−1)=37
Substitute the standard approximation value of π=722:
r(2×722−1)=37
r(744−1)=37
Take the common denominator inside the parentheses:
r(744−7)=37
r(737)=37
Now, solve for r:
r=37×377
r=7 cm
The radius of the circle is 7 cm.
Step 3: Calculate the area of the circle
Now use the radius value to find the area:
Area=πr2
Area=722×7×7
Cancel out the common factor of 7:
Area=22×7
Area=154 cm2
Conclusion
The area of the circle is 154 cm2.
Hence, the correct option is (b) 154.