You need to understand that you're solving for the average, which you already know: 90. Since you know the values of the first three exams, and you know what your final value needs to be, just set up the problem like you would any time you're averaging something.
Solving for the average is simple:
Add up all of the exam scores and divide that number by the number of exams you took.
(87 + 88 + 92) / 3 = your average if you didn't count that fourth exam.
Since you know you have that fourth exam, just substitute it into the total value as an unknown, X:
(87 + 88 + 92 + X) / 4 = 90
Now you need to solve for X, the unknown:
87
+
88
+
92
+
X
4
(4) = 90 (4)
Multiplying for four on each side cancels out the fraction.
So now you have:
87 + 88 + 92 + X = 360
This can be simplified as:
267 + X = 360
Negating the 267 on each side will isolate the X value, and give you your final answer:
X = 93
Now that you have an answer, ask yourself, "does it make sense?"
I say that it does, because there were two tests that were below average, and one that was just slightly above average. So, it makes sense that you'd want to have a higher-ish test score on the fourth exam.
Answer:
$1650
Step-by-step explanation:
Based on the question, we don't need the information that Mike wants to save 1750 in 12 months.
We just need to focus on how he is saving 150 every month, for 11 months.
150*11=1650
He will save $1650 if he saves $150 every month for 11 months.
Answer:
22110 employees.
Step-by-step explanation:
33500 decrease 34% =
33500 × (1 - 34%) = 33500 × (1 - 0.34) = 22110
1/5 is an expression that represents 1÷5= .2
Since the return decimal equivalent doesn't go on forever and has a finite end, this is a member of the rational number set.
Answer:
11/3
Step-by-step explanation:
m=(y2-y1)/(x2-x1)
m=(55-22)/(15-6)
m=33/9
simplify
m=11/3
