Finding the Fourth Proportional to 76,399.31, 105,213.05 and 55,144.91

Step by Step Solution

1. Step 1: Write the proportion equation
   76,399.31 : 105,213.05 = 55,144.91 : x
2. Step 2: Convert to fraction form
   76,399.31/105,213.05 = 55,144.91/x
3. Step 3: Cross multiply
   76,399.31x = 105,213.05 × 55,144.91
4. Step 4: Simplify right side
   76,399.31x = 5,801,963,371.29
5. Step 5: Solve for x
   x = 5,801,963,371.29/76,399.31
6. Step 6: Final answer
   x = 75,942.62