Finding the Fourth Proportional to 139,478.72, 209,307.18 and 50,723.78

Step by Step Solution

1. Step 1: Write the proportion equation
   139,478.72 : 209,307.18 = 50,723.78 : x
2. Step 2: Convert to fraction form
   139,478.72/209,307.18 = 50,723.78/x
3. Step 3: Cross multiply
   139,478.72x = 209,307.18 × 50,723.78
4. Step 4: Simplify right side
   139,478.72x = 10,616,850,304.20
5. Step 5: Solve for x
   x = 10,616,850,304.20/139,478.72
6. Step 6: Final answer
   x = 76,118.07