Question 870270
It is unclear if the 3.5%, 25% and 50% are of the 15000 families of  those who read
3.5% of those who read A , 25% of those who read B and 50% of those who read both

280+500+100=880 who read ads if the second choice

525+7500+3750=11775 if the first.

if 1000 read both then at most 11000 read just one.

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