Finding the Fourth Proportional to 80,651.31, 120,623.27 and 71,828.88

Step by Step Solution

1. Step 1: Write the proportion equation
   80,651.31 : 120,623.27 = 71,828.88 : x
2. Step 2: Convert to fraction form
   80,651.31/120,623.27 = 71,828.88/x
3. Step 3: Cross multiply
   80,651.31x = 120,623.27 × 71,828.88
4. Step 4: Simplify right side
   80,651.31x = 8,664,234,026.89
5. Step 5: Solve for x
   x = 8,664,234,026.89/80,651.31
6. Step 6: Final answer
   x = 107,428.31