Correct Answer: B
Explanation:
If the average high temperature for x days is 70 degrees, then the sum of those x high temperatures is 70x. The sum of the high temperatures, including the additional day that has a temperature of 75 degrees is, therefore, 70x + 75. Next, use the average formula to find the value of x:
In this formula, 71 is the average, 70x + 75 is the total, and there are x + 1 days. Substituting this information into the formula gives:
To solve, cross-multiply to get 71x + 71 = 70x + 75. Next, simplify to find that x = 4. Therefore, Quantity B is greater. The correct answer is (B).