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:
the correct answer is
Step-by-step explanation:
hope this helps u!!
I would say it’s B because out of ten it makes the mean 1 point higher
If the number begins by being rational, multiplying by 0.5 will not change whether or not it is rational. It will remain rational.
That would include any even number 12 * 0.5 = 6
12 started out as rational, so the answer is rational (6)
Any odd number is also rational
23 * 0.5 = 11.5
23 and 11.5 are both rational.
3.636363636 ... is rational so when multiplied by 0.5 the result will be rational.
1.818181818....
So if we start with something irrational like pi
then pi * 0.5 is not rational.
If you have choices, please list them.
Answer:
exactly 12:00 midnight on a 24hour clock is represented as 00:00