Q:

The sum of 3 consecutive odd numbers is 69. What is the third number in this sequence?

Accepted Solution

A:
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Define x :
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Let the numbers be x, x+2 and x+4

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Construct equation :
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The sum of these number is 69
x + x + 2 + x + 4 = 69

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Solve x:
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x + x + 2 + x + 4 = 69
3x + 6 = 69
3x = 63
x = 21

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Find the numbers :
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x = 21
x+ 2 = 23
x + 4 = 25

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Answer: The third number in the sequence is 25.
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