Finding the Fourth Proportional to 31,986.46, 47,978.61 and 8,612.02

Step by Step Solution

1. Step 1: Write the proportion equation
   31,986.46 : 47,978.61 = 8,612.02 : x
2. Step 2: Convert to fraction form
   31,986.46/47,978.61 = 8,612.02/x
3. Step 3: Cross multiply
   31,986.46x = 47,978.61 × 8,612.02
4. Step 4: Simplify right side
   31,986.46x = 413,192,748.89
5. Step 5: Solve for x
   x = 413,192,748.89/31,986.46
6. Step 6: Final answer
   x = 12,917.74