Question

Based on the data in the two-way table, what is the probability that a person weighs 120 pounds, given that he or she consumes 2,000 to 2,500 calories per day?

Answer 1

generic conditional probability formula:

Probability of "A" given "B"

P (A|B) = P(A⋂B)/P(B)

applying this logic to your problem:

Probability of "weighing 120 pounds" given "consuming 2-2.5K calories per day)

P(weigh 120lbs | 2-2.5K cals) = P(weighs 120 lbs AND consumes 2-2.5K) / P(consumes 2-2.5 calories)

Answer 2

put more simply:

find the # of people who weigh 120 and consume 2-2.5K, and divide by the total # of people who consume 2-2.5K