Age(10-14)(15-19)(20-29)(30-39) (40-44)

Mid 12.5 17.5 25 35 42.5
P(X=x) .003 .100 .500 .300 .097

If we select a birth at random, what is the probability the mother is 19 years or younger?

I'm not sure what you mean by "P(X=x). If it is probability, add the probabilities for the two lower categories to indicate the probability that it is either (10-14) or (15-19).

Does "Mid" refer to median?

I hope this helps. If not, repost your question in clearer terms.

To find the probability that the mother is 19 years or younger, we need to consider the age range of 15-19 and calculate the probability P(X=x) for that range.

It is given that the age range of 15-19 corresponds to the midpoint of 17.5. The probability for this range is also given as P(X=x) = 0.100.

Therefore, the probability that the mother is 19 years or younger is 0.100 or 10%.