Finding the Third Proportional to 521.81 and 784.88

Step by Step Solution

1. Step 1: Write the proportion equation
   521.81 : 784.88 = 784.88 : x
2. Step 2: Convert to fraction form
   521.81/784.88 = 784.88/x
3. Step 3: Cross multiply
   521.81x = 784.88 × 784.88
4. Step 4: Simplify right side
   521.81x = 616,028.77
5. Step 5: Solve for x
   x = 616,028.77/521.81
6. Step 6: Final answer
   x = 1,180.56