So he bought the $120 game with $82 and 2 equally priced game. This can be changed to an equation: 120= 82+2X. The X represents the cost of the used game. 120= 82+2X -82 -82 ——————- 38= 2X
Each of the numbers 10, 70 and 490 is separated from the next by a factor of 7. 10 times 7 is 70; 70 times 7 is 490; 7 times 490 is what? 7 times 7 times 490 is what?