This question utilizes combining like terms and common denominators. First you have to convert both terms including "a" to have a denominator of 8. You would do this by multiplying both the numerator, and the denominator by the same value. This value in the case of would be 2, and in the case of the value would be 2. This would result in the equation: . Then simply combine like terms to get your final answer.
A suitable probability app shows the 1st percentile to be at about 11040 pages.
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The app shown has an error in the first decimal digit. The number is closer to 11040.82301. We expect the manufacturer would round to the nearest 10 or 50 or 100 in advertising.