Finding the Fourth Proportional to 81,721.98, 122,572.17 and 31,817.34

Step by Step Solution

1. Step 1: Write the proportion equation
   81,721.98 : 122,572.17 = 31,817.34 : x
2. Step 2: Convert to fraction form
   81,721.98/122,572.17 = 31,817.34/x
3. Step 3: Cross multiply
   81,721.98x = 122,572.17 × 31,817.34
4. Step 4: Simplify right side
   81,721.98x = 3,899,920,407.43
5. Step 5: Solve for x
   x = 3,899,920,407.43/81,721.98
6. Step 6: Final answer
   x = 47,721.81