Simple Permutations/Combinations Question

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A group of 5 men and 5 women stand in line to have their photo taken.

How many ways can they stand in line if no two men and no two women stand together?

My method: _M_M_M_M_M_

Male * Female = 5P5 * 6P5 = 86400

Correct Answer = 5! * 5! * 2 = 28800

I don't understand why I got it wrong, can anyone help please?

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If you distiguish only by man and woman, then they can be arranged: $$m-w-m-w-m-w-m-w-m-w$$ and $$w-m-w-m-w-m-w-m-w-m$$

If you distinguish the womans, there are $5!$ possibilities. The same for men.