Last Updated on May 5, 2023
GMAT OFFICIAL GUIDE PS
Solution:
To solve this question we can use the weighted average equation.
Weighted Average = (Sum of Weighted Terms) / (Total Number of Items)
We’ll first determine the sum (numerator). We see that on the first day we had 8 items that averaged 12 3/8 pounds. We don’t know the weights of the individual packages, but we can determine that the sum of all 8 packages is:
Sum of first day’s packages = 8 x 12 3/8 = 99 pounds
Similarly, the sum of the second day’s packages is:
Sum of second day’s packages = 4 x 15 ¼ = 61
We now can use the weighted average equation to find the average weight of the 12 packages:
Weighted Average = (99 + 61) / 12
Weighted Average = 160 /12
Weighted Average = 13 1/3
Answer: A