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3 votes
The average age of three people is 25. If two of the people are 22, how old is the third person...?

A.23
B.25
C.28
D.31
E. None correct

2 Answers

1 vote

Answer:

D

Explanation:

SEX

User Mingjiang Shi
by
7.3k points
4 votes
D.31

To find the average, we must add all the numbers up and then divide by the amount of numbers there.
Here we have 3 numbers, which two values are given and the average.
So average A, is found by adding all number then dividing by the number of numbers added.
Let's say the average, 25 = 22+22+x/3
Combine like terms, so 25=44+x/3
Then to cancel out the three on the left we must multiply 3 on both sides. 3•25=44+x/3•3
Simplify the equation into
75=44+x
Now we subtract 44 from both sides to move it over to the left, so we can isolate the variable.
75-44=44+x-44
Simplify
31=x


The third person is D. 31
User Maninderjit Singh
by
7.3k points