My answer is 680.

This seems to be a tricky one. Here's my attempt.

Since we are supposed to make groups of three ,consider

__ __ __ as a group of men and women.

The first slot can be filled by any one of the 10 men or women.

Now 2 people are booked. One is in the group and one is a spouse.

The second slot can be filled by only one of the 8 men or women.

The 9th person is the spouse of the first person, and can't fill this slot.

So now 4 people are booked. 2 are in the group and 2 are spouses.

The third slot can be filled by only one of the 6 men or women.

Total no of combinations = 10*8*6 = 680

I am not sure about my answer. There might be a flaw in it. Let me know if you find any.

- ash

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ash

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I'm crossing the bridge.........