Finding the Fourth Proportional to 76,756.81, 105,917.20 and 56,624.86

Step by Step Solution

1. Step 1: Write the proportion equation
   76,756.81 : 105,917.20 = 56,624.86 : x
2. Step 2: Convert to fraction form
   76,756.81/105,917.20 = 56,624.86/x
3. Step 3: Cross multiply
   76,756.81x = 105,917.20 × 56,624.86
4. Step 4: Simplify right side
   76,756.81x = 5,997,546,621.59
5. Step 5: Solve for x
   x = 5,997,546,621.59/76,756.81
6. Step 6: Final answer
   x = 78,137.00