Answer:
100 + 20 x n = 400
Step-by-step explanation:
If he ended the game with 400 points, and he scored 100 points in the first round, and 20 points every round after that, then we have to find out how many rounds he played using multiplication and addition. n represents the number of rounds he played, which is what we want to find out. What number do you have to multiply 20 by to get 300? the answer is 10. Therefore, n is 10.
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