Finding the Fourth Proportional to 76.55, 105.71 and 54.77

Step by Step Solution

1. Step 1: Write the proportion equation
   76.55 : 105.71 = 54.77 : x
2. Step 2: Convert to fraction form
   76.55/105.71 = 54.77/x
3. Step 3: Cross multiply
   76.55x = 105.71 × 54.77
4. Step 4: Simplify right side
   76.55x = 5,788.93
5. Step 5: Solve for x
   x = 5,788.93/76.55
6. Step 6: Final answer
   x = 75.63