Answer: 26
Step-by-step explanation: In this problem we have 3 consecutive even numbers whose sum is 84 and it asks us to find the smallest number.
Consecutive even numbers can be represented as x, x + 2, and x + 4.
Since the sum of these is 84, our equation reads
x + (x + 2) + (x + 4) = 84.
Simplifying on the left we get 3x + 6 = 84.
Subtract 6 from both sides and we have 3x = 78.
Divide both sides by 3 and x = 26.
So our smallest number is 26.