Explanation

First, we determine the number of men and woman at the meeting: 750 total – 450 women 300 men

Now we determine the number of each gender under 30:

\(\frac{1}{2}\) of the female participants are less than 30 → \(\frac{1}{2} \times 450\) = 225 women less than thirty

\(\frac{1}{4}\) of the male participants are less than 30 → \(\frac{1}{4} \times 300\) = 75 men less than thirty.

The total number of people less than 30 years of age is 300 (225 + 75).

Finding the probability:

Probability = number of favorable outcomes/number of possible outcomes → \(\frac{300}{750}\) → \(\frac{30}{75}\) → \(\frac{2}{5}\)

Hence option D is correct.
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