Answer: This would be a good topic for an investigation! I suggest you encourage your nephew's curiosity by cutting open some apples and counting the seeds. Try to find some misshapen apples--you might be surprised by the seed distribution.
I try to discourage children from looking for an answer that they can find out for themselves. I like to encourage, instead, that inate scientific curiosity that is so natural in children.
That said, I can tell you that, no, all apples do not have the same number of seeds, and the pollination of the flowers play a part in determining how many seeds develop.
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