Answer:
plleaseeeeeeeeeeeeeeeeeeeeeeeee eeeeeeeeee
Step-by-step explanation:
X= 9th student test score
Add the 9 test scores and divide that total by 9 to equal the average.
(56 + 92 + 78 + 64 + 85 + 83 + 91 + 77 + x)/9= 78
add in parentheses
(626 + x)/9= 78
multiply both sides by 9
626 + x= 702
subtract 626 from both sides
x= 76
ANSWER: 76 is the score needed by the 9th student for a mean of 78.
Hope this helps! :)
Answer:
21.6, 5.4
Step-by-step explanation:
a=4b
a+b-2=25
5b-2=25
5b=27
b=27/5
a=4*27/5
