Finding the Fourth Proportional to 1,185,978.87, 1,636,648.65 and 642,114.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,185,978.87 : 1,636,648.65 = 642,114.56 : x
2. Step 2: Convert to fraction form
   1,185,978.87/1,636,648.65 = 642,114.56/x
3. Step 3: Cross multiply
   1,185,978.87x = 1,636,648.65 × 642,114.56
4. Step 4: Simplify right side
   1,185,978.87x = 1,050,915,931,860.97
5. Step 5: Solve for x
   x = 1,050,915,931,860.97/1,185,978.87
6. Step 6: Final answer
   x = 886,116.91