Finding the Fourth Proportional to 76,678.17, 105,857.38 and 53,778.31

Step by Step Solution

1. Step 1: Write the proportion equation
   76,678.17 : 105,857.38 = 53,778.31 : x
2. Step 2: Convert to fraction form
   76,678.17/105,857.38 = 53,778.31/x
3. Step 3: Cross multiply
   76,678.17x = 105,857.38 × 53,778.31
4. Step 4: Simplify right side
   76,678.17x = 5,692,830,997.43
5. Step 5: Solve for x
   x = 5,692,830,997.43/76,678.17
6. Step 6: Final answer
   x = 74,243.18