Finding the Fourth Proportional to 1,724.72, 2,380.07 and 938.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,724.72 : 2,380.07 = 938.78 : x
2. Step 2: Convert to fraction form
   1,724.72/2,380.07 = 938.78/x
3. Step 3: Cross multiply
   1,724.72x = 2,380.07 × 938.78
4. Step 4: Simplify right side
   1,724.72x = 2,234,345.52
5. Step 5: Solve for x
   x = 2,234,345.52/1,724.72
6. Step 6: Final answer
   x = 1,295.49