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1 vote
The average of Johnny's two tests is a 92. What must he get on a 3rd test to raise his average to a 94?

2 Answers

6 votes
Let's start by writing an equation for this. So in overall, there will be 3 tests. Therefore, If the first two average to 92, then the third plus those two individual scores divided by 3 will need to equal 94. Lets call the new score x.
(92 x 2 + x) / 3 = 94
184 + x = 282
x = 98
Johnny will need to get a 98 on the 3rd test to raise his average to exactly 94.
I hope this helps :-)
4 votes

Answer:

98

Explanation:

In order to solve this problem, we just have to create a simple equation, the average is calculated by adding up the grades of the three tests and then diving it by the number of tests, like this:


Average=(Test1+Test2+Test3)/(3)

So we just have to insert the values into the formula, creating an equation, since we want to figure out the grade he has to get on his third test:


Average=(Test1+Test2+Test3)/(3)


94=(92+92+x)/(3)


3(94)=92+92+x


282=92+92+x


282-92-92=x


x=98

So in order to rise his average to 94, he´d have to get a 98 on his third test.

User Jeff Camera
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