Finding the Fourth Proportional to 56,910.61, 78,540.99 and 31,421.89

Step by Step Solution

1. Step 1: Write the proportion equation
   56,910.61 : 78,540.99 = 31,421.89 : x
2. Step 2: Convert to fraction form
   56,910.61/78,540.99 = 31,421.89/x
3. Step 3: Cross multiply
   56,910.61x = 78,540.99 × 31,421.89
4. Step 4: Simplify right side
   56,910.61x = 2,467,906,348.27
5. Step 5: Solve for x
   x = 2,467,906,348.27/56,910.61
6. Step 6: Final answer
   x = 43,364.61