Answer:
3/8
Explanation:
Looking at the bottom row, there are 8 possible outcomes
HHH, HHT, HTH, HTT, THH, THT, TTH, TTT
There are 3 that have exactly 2 heads HHT, HTH, THH,
That means the probability is
P( exactly 2 heads) = number outcomes with exactly 2 heads/total outcomes
=3/8