Question

2.5
score: 28/35 answered: 23/29
question 24
the circumference of a circle is given by the formula (c = 2pi r). find (r) if the circumference is 220 meters and (pi) is (\frac{22}{7}).
the radius, (r), is (square) meters.
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Explanation:

Step1: Substitute values into formula

Given $C = 220$, $\pi=\frac{22}{7}$, and $C = 2\pi r$. So, $220=2\times\frac{22}{7}\times r$.

Step2: Simplify the right - hand side

$2\times\frac{22}{7}\times r=\frac{44}{7}r$. So the equation becomes $220=\frac{44}{7}r$.

Step3: Solve for r

Multiply both sides of the equation by $\frac{7}{44}$: $r = 220\times\frac{7}{44}$.
$220\times\frac{7}{44}=\frac{220\times7}{44}=\frac{1540}{44}=35$.

Answer:

35