Question

Find the circumference of a circle whose diameter is 28 cm 22/7

Answer 1

To find the circumference of a circle, you can use the formula:

\[
\text{Circumference} = \pi \times d
\]

where \(d\) is the diameter.

In this case, the diameter is given as \(28 \, \text{cm} \, \frac{22}{7}\). This indicates that \(d = 28 + \frac{22}{7}\).

First, convert \(28\) into a fraction:

\[
28 = \frac{28 \times 7}{7} = \frac{196}{7}
\]

Now, add \(\frac{196}{7}\) and \(\frac{22}{7}\):

\[
d = \frac{196}{7} + \frac{22}{7} = \frac{196 + 22}{7} = \frac{218}{7}
\]

Now that we have the diameter, we can use it to find the circumference:

\[
\text{Circumference} = \pi \times d = \frac{22}{7} \times \frac{218}{7}
\]

Calculating \(d\):

\[
\text{Circumference} = \frac{22 \times 218}{7 \times 7} = \frac{4796}{49}
\]

Now it’s preferable to convert this to a decimal for clarity:

\[
\frac{4796}{49} \approx 97.20 \, \text{cm}
\]

So the circumference of the circle is approximately \(97.20 \, \text{cm}\).