Imagine a pie cut into 32 pieces. Half the pie (1/2) would have 16 pieces, and a fourth of the pie (1/4) would have 8 pieces. If you add up 1/4 and 1/4 and 1/4 parts of the pie you would have 3/4's, and that's the same as adding 8 pieces plus 8 pieces plus 8 pieces which equals 24 pieces. So 3/4 of 32 is 24.
A fast way to do the same thing is divide 32 by 4 and then multiply by 3, which is what we just did. (32 / 4 x 3 = 24)
A less intuitive method is to change the order of operation, and multiply 32 by 3 first, and then divide that by 4. Can you explain why this works?