SOLUTION: The mean of four numbers is 25. Three of the numbers are 15, 36, and 20. What is the fourth number

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Question 1159131: The mean of four numbers is 25. Three of the numbers are 15, 36, and 20. What is the fourth number
Found 2 solutions by ikleyn, greenestamps:
Answer by ikleyn(52776)   (Show Source):
You can put this solution on YOUR website!
.

= 25. Solve for x. Complete the assignment on your own.

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Answer by greenestamps(13198)   (Show Source):
You can put this solution on YOUR website!

Of course you can use the formal definition of mean to write and solve an equation to solve the problem.

If that kind of formal solution method is not required, there are other ways that can get you to the answer faster and with less work. Here is my preferred method.

The 1st number is 10 short of the mean.
The second number is 11 over the mean.
The third number is 5 short of the mean.

Together, the first three numbers are 4 short of the mean.

That means the fourth number is 4 over the mean.

ANSWER: 25+4 = 29