Finding the Fourth Proportional to 1,186,109.60, 1,636,831.89 and 642,245.63

Step by Step Solution

1. Step 1: Write the proportion equation
   1,186,109.60 : 1,636,831.89 = 642,245.63 : x
2. Step 2: Convert to fraction form
   1,186,109.60/1,636,831.89 = 642,245.63/x
3. Step 3: Cross multiply
   1,186,109.60x = 1,636,831.89 × 642,245.63
4. Step 4: Simplify right side
   1,186,109.60x = 1,051,248,120,212.98
5. Step 5: Solve for x
   x = 1,051,248,120,212.98/1,186,109.60
6. Step 6: Final answer
   x = 886,299.31