Lisa's test grades are 79, 89, and 90. there will be one more test this year. if lisa wants her test average to be at least 88, what is the lowest grade she can get on her last test?
Mathematics · High School · Sun Jan 24 2021
Answered on
Given the statement:
Lisa's test grades are 79, 89, and 90. there will be one more test this year.
Determine the lowest grade she can get on her last test in order to have an average of 88.
Solution:
Multiply 88 by 4
= 88(4)
= 352
Subtract the sum of 79, 89, and 90 to 352.
= 352 - (79 + 89 + 90)
= 352 - 258
= 94
Lisa must have a grade of 94 in her last test.
Check:
= (79 + 89 + 90 + 94)/4
= 352/4
= 88
Final answer:
Lisa must have a grade of 94 in her last test.