How many nine digit numbers can be formed using the digits: 2, 2, 3, 3, 5, 5, 8, 8, 8 so that odd digits occupy even positions?

There are only 6 distinct ways the numbers 3355 (odd numbers ) can be arranged and there are 10 distinct ways the numbers 22888 (even numbers) can be arranged

So the possible arrangements are 6 x 10 = 60