The sum of four consecutive even integers is 284. What is the smallest of these even integers?

Difficulty: Easy

Correct Answer: 68

Explanation:

Introduction / Context:Consecutive even integers form an arithmetic sequence with common difference 2. Summation and simple algebra quickly identify the first term when the total is known.

Given Data / Assumptions:

  • Let the four numbers be x, x + 2, x + 4, x + 6.
  • Their sum equals 284.
  • All are even integers by construction.

Concept / Approach:Use linear equations for arithmetic sequences. The sum is 4x + 12; isolate x to get the smallest integer directly.

Step-by-Step Solution:

Write the sum: x + (x + 2) + (x + 4) + (x + 6) = 284.Combine: 4x + 12 = 284.Solve: 4x = 272 → x = 272 / 4 = 68.Thus, the numbers are 68, 70, 72, and 74; the smallest is 68.

Verification / Alternative check:Average method: the average of four equally spaced numbers is the mean of the first and last: (68 + 74) / 2 = 71. Multiply by count: 71 * 4 = 284; matches.

Why Other Options Are Wrong:66, 70, 72, or 74 would yield sums different from 284 when building the required four-term set.

Common Pitfalls:Using difference 1 instead of 2 (confusing even with consecutive integers in general).

Final Answer:68

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