Finding the Fourth Proportional to 139,421.72, 209,133.28 and 34,240.72

Step by Step Solution

1. Step 1: Write the proportion equation
   139,421.72 : 209,133.28 = 34,240.72 : x
2. Step 2: Convert to fraction form
   139,421.72/209,133.28 = 34,240.72/x
3. Step 3: Cross multiply
   139,421.72x = 209,133.28 × 34,240.72
4. Step 4: Simplify right side
   139,421.72x = 7,160,874,083.16
5. Step 5: Solve for x
   x = 7,160,874,083.16/139,421.72
6. Step 6: Final answer
   x = 51,361.25