What is the probability of spinning both spinners to get a s

What is the probability of spinning both spinners to get a sum that is less than 7?

Solution

Note that

P(less than 7) = 1 - P(7 or more)

There are 4*4 = 16 possibilities here,

Those with 7 or more as a sum are (3,4), (4,3), (4,4).

Thus,

P(7 or more) = 3/16

Thus,

P(less than 7) = 1 - 3/16 = 13/16 = 0.8125 [answer]