Let x represent the number
The three consecutive numbers are x, x+1,x+2
There sum
x + x + 1 + x + 2 = 66
Re-arrange
x + x + x + 1 + 2 = 66
3x + 3 = 66
3x = 66 - 3
3x = 60
Divide both sides by 3
x = 60/3
x = 20
Since represent the smallest number, the smallest number is 20
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