Answer:
Jenny James would need to have a score of 97 out of 100 points in order to have an average of 90.
Step-by-step explanation:
Given that:
Scores of four tests
78, 89, 90 and 96
Let,
x be the score on fifth test.
Average is the sum of quantities divided by total number of quantities.
Average = 90
Average = [tex]\frac{Sum\ of\ scores}{No.\ of scores}[/tex]
Putting the values in the formula;
[tex]90=\frac{78+89+90+96+x}{5}\\90=\frac{353+x}{5}\\90*5=353+x\\450=353+x\\450-353=x\\x=97[/tex]
Hence,
Jenny James would need to have a score of 97 out of 100 points in order to have an average of 90.
