She needs to score a 91 on her next test because 85+78+77+69+91=400 and 400 divided by 5 gives you a mean of 80.
Answer:
The time required to finish the work by both candy and Tim working together = 36.83 minute
Step-by-step explanation:
Time taken by the candy to finish the work
= 85 min
Time taken by the Tim to finish the work
= 65 min
Thus the time taken by both to finish the work = 
Put the values of
and
we get ,
= 
= 
= 36.83 minute
Thus the time required to finish the work by both candy and Tim working together = 36.83 minute
Answer: 84 mm is MAYBE the answer.
11 liters of 25% orange juice, 4 liters of 10% orange juice:
1' let x to be 25% orange juice and y be 10% orange juice
2' .25x+.10y=(15).21
3' x+y=15
4' 2.5x+y=31.5 divide all sides by 10
5' -x-y=-15 multiply all sides by -1
6' 1.5x=16.5
7' x=11
8' y=15-11=4
so 11 and 4 are the answers.