Hello!
To find the circumference of a circle you do

where r is the radius of the circle
So we do 2

Then we substitute pi for 3.14
2 * 3.14 * 72 = 452.16 yds
Then we multiply this by 5 since he runs 5 laps
Which gives us the answer of 2260.8 yds
Hope this helps!
20x2 = 40 in width
180-40= 140
140/2=70
70 inches
If you count the zeros it’s
one billionth
Mr.Thompson's account will be worth $9,562.50 after 10 years.
You can get the number by dividing 19.2 by 0.40
The number is 19.2/0.40 = 48