Add 3 1/2 and 2 1/3,
Firstly, find the common denominator. It is is 6
3 3/6 + 2 2/6
this gets you 5 5/6.
Take this away from 8:
8 - 5 5/6 = 2 1/6
So 2 1/6 of the board is left over.
Assuming that the label only covers the body of the cylinder and not the circular faces on the top and bottom.
80% is the same as 4/5, so 4/5 of the class= 20. That means that if there was a picture, 4 parts would be shaded, and 1 would not. 1/4 of 20 is 5, so 1 part= 5 people. 5 x 5 = 25. 25 is the answer. :)
C=2πr
Hoped i helped BYEEEEEEEEEEEEEEEEEEEEEEEEE