Step-by-step explanation: Justis has three times the amount of Preston. Three is one of the key words here. Represent Prestons amount by x. Since Justis has three times the amount you would do X times 3 to find out how much Justis has. First we need to see how much Preston has. The total number of them combined is 128. Lets write the equation
3x + x = 128
The two x's are important because your multiplying to see how much Justis has AND adding to get 128
The equation simplified is 4x = 128
divide 128 by 4 and you get 32
The answer is that Preston has 32 and Justis has 96 video games. Hope this helps! :)