Chapter 11.7, Problem 33STP

a.

To determine

To deduce an expression to find the circumference of the given circle.

Answer to Problem 33STP

Circumference $c=15\pi$ feet

Explanation of Solution

Given information:Diameter ‘d’$=15$ feet.

Formula of circumference $c=2\times \pi \times \frac{d}{2}$ Where ‘d’ is the diameter.

  $=d\times \pi$

  $=15\pi$ feet

b.

To determine

To calculate the circumference of the given circle.

Answer to Problem 33STP

  $47$ feet

Explanation of Solution

Given information:Diameter ‘d’$=15$ feet.

Formula used: Circumference (c) of a circle can be calculated using formula $c=2\times \pi \times \frac{d}{2}$

For calculation, take $\pi =\frac{22}{7}$ .

Calculation:

  $c=2\times \pi \times \frac{d}{2}$

Diving 2 on both the numerator and denominator.

  $=d\times \pi$

Putting the values in the expression.

  $=15\times \frac{22}{7}$

Simplifying the expression.

  $=47.14$

Rounding off to the nearest tenth.

  $=47$ feet.