Mary scored 89 on her first test and 92 on her second test, 98 on the third, and 95 on the fourth. She has one more test to take. If she wants to have an average of 100 on all five sets, what score should she get on her removal test?
let score of her last test be x
Review how an average is obtained and use that fact to form the equation, then solve for x
Let me know what you get.
btw, curious about that "removal" test. Are you replacing the lowest score with the last test?
In that case, there would be only four tests.
To find out what score Mary should get on her removal test, we need to calculate the average score she currently has and the total score she needs to achieve.
First, let's determine Mary's current average score. We can do this by adding up all her test scores and dividing the sum by the number of tests she has taken. In this case, she has taken four tests.
Mary's current average score = (89 + 92 + 98 + 95) / 4 = 374 / 4 = 93.5
Next, let's calculate the total score Mary needs to achieve. Since she wants to have an average of 100 on all five tests, the sum of her five test scores should be 100 multiplied by 5 (the number of tests).
Total score needed = 100 * 5 = 500
Now, we need to find out the score Mary should get on her removal test to reach a total score of 500. To do this, we subtract Mary's current total score (374) from the total score needed (500).
Score needed on the removal test = 500 - 374 = 126
Therefore, Mary should aim to get a score of 126 on her removal test in order to achieve an average of 100 on all five tests.