given 20 ping pong balls
numbered 1-20
odd numbers = 1, 3, 5, 7, 9, 11, 13, 15, 17, 19
total odd numbers = 10
numbers less than 5 = 1, 2, 3, 4
total numbers less than 5 = 4
since 1 and 3 are in both sides,
total number of porbabilities
= 10 + 4 - 2
= 12
the probability of selecting one ball
= 12/20
= 3/5
= 0.6
therefore the probabilty of selecting one ball that is either odd or less than 5 = 0.6
