We know the formula for the circumference of a circle is 2•3.24•r (2PiR). Since we have our radius, let's plug in our numbers. 2 • (Pi; 3.14) • 7.8(radius) 2 x 3.14 = 6.28 6.28 x 7.8 = 48.984
Since we're rounding, let's determine if we round up or not.
To see if 48 rounds up or down, look for the Tenths place for a 5 or higher. The Tenths place is 1 place to the right of a decimal. 48.9 9 is higher than 5, so we round 48 to 49.
