Finding the Fourth Proportional to 139,391.71, 209,056.04 and 64,470.74

Step by Step Solution

1. Step 1: Write the proportion equation
   139,391.71 : 209,056.04 = 64,470.74 : x
2. Step 2: Convert to fraction form
   139,391.71/209,056.04 = 64,470.74/x
3. Step 3: Cross multiply
   139,391.71x = 209,056.04 × 64,470.74
4. Step 4: Simplify right side
   139,391.71x = 13,477,997,277.92
5. Step 5: Solve for x
   x = 13,477,997,277.92/139,391.71
6. Step 6: Final answer
   x = 96,691.53