※ Our check while writing this explanation could not fully confirm the published answer; scoring follows IPA's official key.
×Incorrectア
Option 1, “Stop posting photos”, has high individual scores of 5 for cost and 5 for implementation, and if the weights are ignored its simple total of 11 points is the highest, which makes it a tempting trap. However, its weighted sum is only 1×4 + 5×2 + 5×1 = 19 points, the lowest of the four options. The decisive disadvantage is that effect carries the largest weight of 4 yet scores only 1. This wrong answer is chosen only when the weighting in instruction (3) is overlooked.
×Incorrectイ
Option 2, “Narrow down the number of photos posted per product”, scores 2×4 + 5×2 + 3×1 = 21 points. Its cost score of 5 (smallness of cost) is attractive, but effect — which carries the largest weight of 4 — is only 2, so the total does not grow enough to reach Option 4’s 26 points. This is a typical example of weighted evaluation: a cheap and easy-to-implement option does not necessarily win the overall evaluation.
×Incorrectウ
Option 3, “Have the system check the registered content”, is the only option with a full score of 5 for effect, and effect also carries the largest weight of 4, so at first glance it looks advantageous. However, it scores 5×4 + 1×2 + 1×1 = 23 points, short of Option 4’s 26 points. Cost of 1 and implementation of 1 drag it down. This wrong answer shows that the option with the highest effect does not necessarily rank first overall.
○エ
正解The correct answer is “エ Option 4”. Item (3) of the supervisor’s instructions states that improvement measures are to be evaluated from three viewpoints — “magnitude of effect”, “smallness of cost”, and “ease of implementation” — and given an overall evaluation as the sum of each viewpoint’s score multiplied by its weight. The weights emphasize effect: effect : cost : implementation = 4 : 2 : 1. Multiplying the scores in Table 1 by these weights and summing gives: Option 1 = 1×4 + 5×2 + 5×1 = 19 points, Option 2 = 2×4 + 5×2 + 3×1 = 21 points, Option 3 = 5×4 + 1×2 + 1×1 = 23 points, Option 4 = 4×4 + 4×2 + 2×1 = 26 points. The highest score of 26 points is obtained by Option 4, “Have a veteran staff member visually check the registered content in bulk”, so the correct answer is エ. Option 4 achieves a high level on both effect (4) and cost (4), and even though implementation is only 2, that axis carries the smallest weight of 1, so it does not affect the overall evaluation — this is how the weighting works, which is the key point of the question.
ここがポイント
How to compute a weighted evaluation (weighted overall evaluation): multiply each evaluation axis’s score by that axis’s weight, sum over all axes, and compare the options by the size of the total. When weights are given, you must not judge by a simple sum.
Aligning the direction of the evaluation axes: in Table 1, “Cost” does not mean the amount of cost but the “smallness of cost”, and “Implementation” means the “ease of implementation”; both are aligned so that 5 is the good direction. If you mistake this direction, your interpretation of the scores is reversed.