Finding the Fourth Proportional to 81,910.18, 122,792.19 and 31,978.72

Step by Step Solution

1. Step 1: Write the proportion equation
   81,910.18 : 122,792.19 = 31,978.72 : x
2. Step 2: Convert to fraction form
   81,910.18/122,792.19 = 31,978.72/x
3. Step 3: Cross multiply
   81,910.18x = 122,792.19 × 31,978.72
4. Step 4: Simplify right side
   81,910.18x = 3,926,737,062.20
5. Step 5: Solve for x
   x = 3,926,737,062.20/81,910.18
6. Step 6: Final answer
   x = 47,939.55