Finding the Fourth Proportional to 78,781.31, 108,716.36 and 42,971.61

Step by Step Solution

1. Step 1: Write the proportion equation
   78,781.31 : 108,716.36 = 42,971.61 : x
2. Step 2: Convert to fraction form
   78,781.31/108,716.36 = 42,971.61/x
3. Step 3: Cross multiply
   78,781.31x = 108,716.36 × 42,971.61
4. Step 4: Simplify right side
   78,781.31x = 4,671,716,807.68
5. Step 5: Solve for x
   x = 4,671,716,807.68/78,781.31
6. Step 6: Final answer
   x = 59,299.81