Question

It is: THE SUM OF THREE CONSECUTIVE NUMBERS IS 78 WHAT IS THE SMALLEST OF THREE NUMBERS?

Answer 1

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Define x :
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Let the smallest number be x.
The other two numbers will be x+1 and x+2.

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Construct equation :
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The sum of all 3 numbers is 78
⇒ x + x + 1 + x + 2 = 78

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Solve x :
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x + x + 1 + x + 2 = 78
3x + 3 = 78
3x = 78 - 3
3x = 75
x = 25

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Answer: Smallest number = 25
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Answer 2

Lets call them
a, b, c
we know that
a+b+c=78
and we know they are consecutive which makes this problem a lot more easier
the number just after another number is that number plus one. example:
the number just after 3 is
3+1...which is 4
lets write our consecutive numbers in a way that we can use this principle:
a, a+1, a+2

a+a+1+a+2=78
3a+3=78
3a=75
a=25
the smallest number is 25