Finding the Fourth Proportional to 1,065.57, 1,470.15 and 623.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,065.57 : 1,470.15 = 623.31 : x
2. Step 2: Convert to fraction form
   1,065.57/1,470.15 = 623.31/x
3. Step 3: Cross multiply
   1,065.57x = 1,470.15 × 623.31
4. Step 4: Simplify right side
   1,065.57x = 916,367.05
5. Step 5: Solve for x
   x = 916,367.05/1,065.57
6. Step 6: Final answer
   x = 859.98