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:
West.
Step-by-step explanation:
An old treasure map has the following instructions: stand next to the black rock and face west. Walk 20 yards and then turn 90 degrees clockwise. Walk another 10 yards and then turn 45 degrees anticlockwise. Walk another 15 yards, reverse your directions and walk 5 yards back. Turn 135 degrees clockwise and walk another 10 yards. To determine in which direction you are now facing, the following logical reasoning must be carried out:
You start by walking 20 yards west, then turning 90 degrees clockwise, turning south. Then you walk 10 yards and turn counterclockwise 45 degrees, to the southwest. Later, you walk another 15 yards, turn the direction to the northeast, and walk 5 more yards. From the northeast turn 135 degrees clockwise to the west and walk 10 yards. Thus, the final sense in which the person is walking is to the West.
Answer:
98.01
Step-by-step explanation:
![[9.9]^2\\=[\frac{99}{10}]^2\\ =\frac{9801}{100}\\ =98.01](https://tex.z-dn.net/?f=%5B9.9%5D%5E2%5C%5C%3D%5B%5Cfrac%7B99%7D%7B10%7D%5D%5E2%5C%5C%20%3D%5Cfrac%7B9801%7D%7B100%7D%5C%5C%20%3D98.01)
Answer:
one person one number
Step-by-step explanation:
Answer:
Exact form
-32768/5
Decimal Form:
−6553.6
Mixed Number Form:
−6553 3/5
Step-by-step explanation:
<em>Hope this helps :)</em>
<em>Have an amazing day <3</em>
<em>Pls mark brainliest :p</em>
And also if you have more questions like this use math.way it'll help :)