Shilpa earned 100 points in the first round of a game. she earned 20 points in each of the following rounds of the game. she ended the game with 400 points. write and solve an equation to find the number of rounds shilpa played.

15 rounds Shilpa played.

Step-by-step explanation:

They tell us she earned 100 points in the first round, that's going to be a fixed value in the equation. Then, we know the won 20 points in every next round (20x). So, we will have the following: 100 + 20x = 400

Clear x:

20x = 400 - 100

20x = 300

x = 300/20

x = 15