Question 101391: The sum of three consecutive even numbers is 60. What are the the 3 numbers? Can someone help me figure this one out?
Answer by bucky(2189)   (Show Source):
You can put this solution on YOUR website! The numbers are consecutive. Therefore, if you let x be the first number, then x + 1 is the
next consecutive number. And the third consecutive number is 1 more than x + 1, so the third
number is x + 2. The sum of these three numbers is 60, so you can write the equation:
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x + x + 1 + x + 2 = 60
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On the left side add the three x terms to make the equation:
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3x + 1 + 2 = 60
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Again on the left side add the 1 and the 2 and the equation becomes:
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3x + 3 = 60
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Get rid of the 3 on the left side by subtracting 3 from both sides:
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3x = 57
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Solve for x by dividing both sides by 3 to get:
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x = 57/3 = 19
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If 19 is the first number, then the next consecutive number is 19 + 1 = 20 and the third
consecutive number is 19 + 2 = 21. So the three numbers are 19, 20, and 21.
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Check this answer. Add 19 + 20 + 21 and you will see that the total is 60, just as it was
supposed to be.
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Hope this helps you to see your way through the problem. The trick is just to see that
unknown consecutive numbers can be written as x, x + 1, x + 2, x + 3 and so on.
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