Finding the Fourth Proportional to 1,126,085.69, 1,553,980.73 and 642,638.40

Step by Step Solution

1. Step 1: Write the proportion equation
   1,126,085.69 : 1,553,980.73 = 642,638.40 : x
2. Step 2: Convert to fraction form
   1,126,085.69/1,553,980.73 = 642,638.40/x
3. Step 3: Cross multiply
   1,126,085.69x = 1,553,980.73 × 642,638.40
4. Step 4: Simplify right side
   1,126,085.69x = 998,647,686,744.84
5. Step 5: Solve for x
   x = 998,647,686,744.84/1,126,085.69
6. Step 6: Final answer
   x = 886,830.99