d=7.9cm. what is the circumference and area of the circle?
circumfrence: pi times diameter
7.9\(\pi\)
circumfrence is approximatley 24.806
area: \(\pi r^2\)
a=\(\pi\)(1/2(d))^2
a= 48.99
You multiply 7.9 by pi to get an answer of 24.8 cm for the curcumference, and then square the raduis, 3.95, to get 15.6025, and then multiply that by pi to get 48.9 cm squared for the area. (I used 3.14 for pi and rounded to the first decimal place)