QuestionAugust 26, 2025

Calculate the weighted average of -9 and 21 with weights of (2)/(3) on the first number and (3)/(7) on the second number square

Calculate the weighted average of -9 and 21 with weights of (2)/(3) on the first number and (3)/(7) on the second number square
Calculate the weighted average of -9 and 21 with weights of (2)/(3) on
the first number and (3)/(7) on the second number
square

Solution
4.6(225 votes)

Answer

The weighted average is approximately 5.25. Explanation 1. Calculate the weighted sum Multiply each number by its weight: -9 \times \frac{2}{3} and 21 \times \frac{3}{7}. 2. Sum the weighted values Add the results from Step 1: (-9 \times \frac{2}{3}) + (21 \times \frac{3}{7}). 3. Calculate the total weight Add the weights: \frac{2}{3} + \frac{3}{7}. 4. Divide the weighted sum by the total weight Use the formula for weighted average: **Weighted Average = \frac{\text{Weighted Sum}}{\text{Total Weight}}**.

Explanation

1. Calculate the weighted sum<br /> Multiply each number by its weight: $-9 \times \frac{2}{3}$ and $21 \times \frac{3}{7}$.<br />2. Sum the weighted values<br /> Add the results from Step 1: $(-9 \times \frac{2}{3}) + (21 \times \frac{3}{7})$.<br />3. Calculate the total weight<br /> Add the weights: $\frac{2}{3} + \frac{3}{7}$.<br />4. Divide the weighted sum by the total weight<br /> Use the formula for weighted average: **Weighted Average = \frac{\text{Weighted Sum}}{\text{Total Weight}}**.
Click to rate: