Finding the Fourth Proportional to 31,789.34, 47,686.29 and 8,415.50

Step by Step Solution

1. Step 1: Write the proportion equation
   31,789.34 : 47,686.29 = 8,415.50 : x
2. Step 2: Convert to fraction form
   31,789.34/47,686.29 = 8,415.50/x
3. Step 3: Cross multiply
   31,789.34x = 47,686.29 × 8,415.50
4. Step 4: Simplify right side
   31,789.34x = 401,303,973.50
5. Step 5: Solve for x
   x = 401,303,973.50/31,789.34
6. Step 6: Final answer
   x = 12,623.85