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. Let's be accurate as possible.
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.
The answer: 20.