Finding the Fourth Proportional to 1,186,002.56, 1,636,684.48 and 642,138.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,186,002.56 : 1,636,684.48 = 642,138.56 : x
2. Step 2: Convert to fraction form
   1,186,002.56/1,636,684.48 = 642,138.56/x
3. Step 3: Cross multiply
   1,186,002.56x = 1,636,684.48 × 642,138.56
4. Step 4: Simplify right side
   1,186,002.56x = 1,050,978,215,161.55
5. Step 5: Solve for x
   x = 1,050,978,215,161.55/1,186,002.56
6. Step 6: Final answer
   x = 886,151.73