Finding the Fourth Proportional to 1,288,403.59, 1,778,000.15 and 715,443.71

Step by Step Solution

1. Step 1: Write the proportion equation
   1,288,403.59 : 1,778,000.15 = 715,443.71 : x
2. Step 2: Convert to fraction form
   1,288,403.59/1,778,000.15 = 715,443.71/x
3. Step 3: Cross multiply
   1,288,403.59x = 1,778,000.15 × 715,443.71
4. Step 4: Simplify right side
   1,288,403.59x = 1,272,059,023,696.56
5. Step 5: Solve for x
   x = 1,272,059,023,696.56/1,288,403.59
6. Step 6: Final answer
   x = 987,314.09