Explanation

Find Airline B's rating for convenience (8.0) and Airline A's rating for convenience (5.1).

Category	A	B	C
Convenience	5.1	8.0	4.3
Friendliness	5.0	5.5	5.4
Price	5.0	6.4	3.5
Promptness	6.5	6.9	4.1
Reliability	7.8	7.5	4.9
Total:	29.4	34.3	22.2

Determine the increase: 8.0 – 5.1 = 2.9
Now we find the percent change and round to the nearest whole number: Percent change = increase ÷ original number × 100 → 2.9 ÷ 5.1 × 100 = 56.86% or 57%.

Hence option D is correct.
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Sandy
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Because you cannot subtract 5.1 - 8.0 that is a negative number. You subtract A from B: B - A = 8 - 5.1. And A is 5.1.

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