Answer:
Sue must score 94 on the final test to earn a B.
Step-by-step explanation:
There are five tests in total.
Sue's average on the first four tests is 84.
If after the final test, she scores X, she will have a B on average of five tests.
We have the following equation:
86 = (4 × 84 + X)/5
<=> X = 5 × 86 - 4 × 84
=> X = 94
X=15
EXPLANATION:
5x+4+5x+11+x=180
11x+15=180
-15 -15
11x=165
— ——
11 11
x=15
Answer:
A3
B1
C2
Step-by-step explanation:
H = 2f / (m+1)
[multiply by (m+1)]
h(m+1) = 2f
[divide by 2]
f = (h (m + 1)) / 2
3b / (b+2) = 12 / (b+2)
[multiply by (b+2)]
3b = 12
[divide by 3]
b = 4
3 / (6x + 1) / 2 = 8 / (x + 4) / 3
[multiply both denominators to mike one denominator]
3 / 8(6x+1) = 8 / 3(x+4)
[expand brackets]
3 / (48x + 8) = 8 / (3x + 12)
[multiply by (48x + 8)]
3 = 8(48x + 8) / (3x+12)
[multiply by (3x+12)]
3(3x +12) = 4(48x + 8)
[simplify]
9x + 36 = 192x + 32
173x = 4
x = 4 / 173
