Finding the Fourth Proportional to 1,149.72, 1,724.82 and 419.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,149.72 : 1,724.82 = 419.31 : x
2. Step 2: Convert to fraction form
   1,149.72/1,724.82 = 419.31/x
3. Step 3: Cross multiply
   1,149.72x = 1,724.82 × 419.31
4. Step 4: Simplify right side
   1,149.72x = 723,234.27
5. Step 5: Solve for x
   x = 723,234.27/1,149.72
6. Step 6: Final answer
   x = 629.05