Finding the Fourth Proportional to 56,940.81, 78,578.37 and 31,790.31

Step by Step Solution

1. Step 1: Write the proportion equation
   56,940.81 : 78,578.37 = 31,790.31 : x
2. Step 2: Convert to fraction form
   56,940.81/78,578.37 = 31,790.31/x
3. Step 3: Cross multiply
   56,940.81x = 78,578.37 × 31,790.31
4. Step 4: Simplify right side
   56,940.81x = 2,498,030,741.59
5. Step 5: Solve for x
   x = 2,498,030,741.59/56,940.81
6. Step 6: Final answer
   x = 43,870.66