Task
Eric is playing a video game. At a certain point in the game, he has 31500 points. Then the following events happen, in order:
- He earns 2450 additional points.
- He loses 3310 points.
- The game ends, and his score doubles.
Write an expression for the number of points Eric has at the end of the game. Do not evaluate the expression. The expression should keep track of what happens in each step listed above.
Eric's sister Leila plays the same game. When she is finished playing, her score is given by the expression
$$ 3(24500 + 3610) - 6780. $$
Describe a sequence of events that might have led to Leila earning this score.
IM Commentary
Standard 5.OA.2 asks students to "Write simple expressions that record calculations with numbers, and interpret numerical expressions without evaluating them." This task asks students to exercise both of these complementary skills, writing an expression in part (a) and interpreting a given expression in (b). The numbers given in the problem are deliberately large and "ugly" to discourage students from calculating Eric's and Leila's scores. The focus of this problem is not on numerical answers, but instead on building and interpreting expressions that could be entered in a calculator or communicated to another student unfamiliar with the context.