Finding the Fourth Proportional to 2,631,188, 3,947,406 and 858,260

Step by Step Solution

1. Step 1: Write the proportion equation
   2,631,188 : 3,947,406 = 858,260 : x
2. Step 2: Convert to fraction form
   2,631,188/3,947,406 = 858,260/x
3. Step 3: Cross multiply
   2,631,188x = 3,947,406 × 858,260
4. Step 4: Simplify right side
   2,631,188x = 3,387,900,673,560
5. Step 5: Solve for x
   x = 3,387,900,673,560/2,631,188
6. Step 6: Final answer
   x = 1,287,593.54