Answer:
84 is the highest possible course average
Step-by-step explanation:
Total number of examinations = 5
Average = sum of scores in each examination/total number of examinations
Let the score for the last examination be x.
Average = (66+78+94+83+x)/5 = y
5y = 321+x
x = 5y -321
If y = 6, x = 5×6 -321 =-291.the student cannot score -291
If y = 80, x = 5×80 -321 =79.he can still score higher
If If y = 84, x = 5×84 -321 =99.This would be the highest possible course average after the last examination.
If y= 100
The average cannot be 100 as student cannot score 179(maximum score is 100)
2•2•2 is the answer, I think unclear about what u askingb
8x + 3y = 20.50
-
4x+5y=22.50
=
4x-2y=-2, so you have to divide each number by 2, then
2x-y=-1, so
-y=-1-2x /-1, y=1+2x, then replace it with one original equation like the first one for instance:
8x+3(1+2x)=20.50, then
8x+3+6x=20.50, then
14x=20.50-3
14x=17.5
x=1.25, then solve y:\
y=1+2*(1.25)
y=1+2.5
y=3.5,
So answer is x=1.25, and y=3.5