Finding the Fourth Proportional to 76,639.72, 105,732.80 and 56,544.84

Step by Step Solution

1. Step 1: Write the proportion equation
   76,639.72 : 105,732.80 = 56,544.84 : x
2. Step 2: Convert to fraction form
   76,639.72/105,732.80 = 56,544.84/x
3. Step 3: Cross multiply
   76,639.72x = 105,732.80 × 56,544.84
4. Step 4: Simplify right side
   76,639.72x = 5,978,644,258.75
5. Step 5: Solve for x
   x = 5,978,644,258.75/76,639.72
6. Step 6: Final answer
   x = 78,009.74