Finding the Fourth Proportional to 1,403.71, 2,105.57 and 429.82

Step by Step Solution

1. Step 1: Write the proportion equation
   1,403.71 : 2,105.57 = 429.82 : x
2. Step 2: Convert to fraction form
   1,403.71/2,105.57 = 429.82/x
3. Step 3: Cross multiply
   1,403.71x = 2,105.57 × 429.82
4. Step 4: Simplify right side
   1,403.71x = 905,016.10
5. Step 5: Solve for x
   x = 905,016.10/1,403.71
6. Step 6: Final answer
   x = 644.73