Answer:
It is not possible for Alice to score an average of 75% because what she needs to score in the fifth exam exceeds the maximum possible score.
Step-by-step explanation:
She scored an average 68% in all 4 exams.
This means; (68% + 68% + 68% + 68%)/4
Now, a fifth exam is added and we want to know if her average can now be 75%.
Thus, let the score in the 5th exam be x and we now have;
(68% + 68% + 68% + 68% + x)/5 = 75%
Multiply both sides by 5 to get;
(68% + 68% + 68% + 68% + x) = 375%
272% + x = 375%
x = 375% - 272%
x = 103%
The maximum score is 100% and therefore it is impossible for her to score 103%. Therefore it is not possible for Alice to score an average of 75%
Answer:
a. a(b)c
b. a(a(b)c)c
d. a(a(a(a)c)c)c
Step-by-step explanation:
We are given the following in the question:

a. a(b)c
It is given b belongs to W.

b. a(a(b)c)c

c. a(abc)c
a(abc)c does not belong to W because we cannot find x in W such that a(abc)c belongs to W.
d. a(a(a(a)c)c)c

e. a(aacc)c
a(aacc)c does not belong to W because we cannot find x in W such that a(aacc)c belongs to W.
6v +12 -5v=v +12.
4b +32+2= 4b+34
like that?
Answer:
9.99
Step-by-step explanation:
Charmaine= x
William=x+3
3 times Charmaine = 3x
2times William = 2x+6
5x+6=76
5x=76-6
5x=70
X=14
Charmaine is 14
William is 3 years older so is 17
Check:
17x2= 34
14x3=42
34+42=76
So Charmaine is 14
William is 17