Finding the Fourth Proportional to 76.82, 105.91 and 55.79

Step by Step Solution

1. Step 1: Write the proportion equation
   76.82 : 105.91 = 55.79 : x
2. Step 2: Convert to fraction form
   76.82/105.91 = 55.79/x
3. Step 3: Cross multiply
   76.82x = 105.91 × 55.79
4. Step 4: Simplify right side
   76.82x = 5,908.72
5. Step 5: Solve for x
   x = 5,908.72/76.82
6. Step 6: Final answer
   x = 76.92