Chris has twelve marbles, and Ryan has twenty-eight marbles. If they put marbles together in a pile and then each takes away 1/4 of marbles from the pile, calculate the number of marbles remaining in the pile.
Step-by-step reasoning process below:
20
If Chris and Ryan put together their marbles in a pile, the pile will have 12 + 28 = 40 marbles.

If they then take 1 / 4 of the marbles each, every person will receive 1 / 4 * 40 = 10 marbles.

Both of them will have taken a total of 10 + 10 = 20 marbles.

The number of marbles remaining in the pile is 40 - 20 = 20.

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Thus, the answer is 20