Finding the Fourth Proportional to 139,799.72, 209,648.55 and 51,026.96

Step by Step Solution

1. Step 1: Write the proportion equation
   139,799.72 : 209,648.55 = 51,026.96 : x
2. Step 2: Convert to fraction form
   139,799.72/209,648.55 = 51,026.96/x
3. Step 3: Cross multiply
   139,799.72x = 209,648.55 × 51,026.96
4. Step 4: Simplify right side
   139,799.72x = 10,697,728,174.91
5. Step 5: Solve for x
   x = 10,697,728,174.91/139,799.72
6. Step 6: Final answer
   x = 76,521.81