Finding the Fourth Proportional to 78.03, 107.69 and 54.77

Step by Step Solution

1. Step 1: Write the proportion equation
   78.03 : 107.69 = 54.77 : x
2. Step 2: Convert to fraction form
   78.03/107.69 = 54.77/x
3. Step 3: Cross multiply
   78.03x = 107.69 × 54.77
4. Step 4: Simplify right side
   78.03x = 5,897.37
5. Step 5: Solve for x
   x = 5,897.37/78.03
6. Step 6: Final answer
   x = 75.58