Finding the Fourth Proportional to 105.54, 158.04 and 64.78

Step by Step Solution

1. Step 1: Write the proportion equation
   105.54 : 158.04 = 64.78 : x
2. Step 2: Convert to fraction form
   105.54/158.04 = 64.78/x
3. Step 3: Cross multiply
   105.54x = 158.04 × 64.78
4. Step 4: Simplify right side
   105.54x = 10,237.83
5. Step 5: Solve for x
   x = 10,237.83/105.54
6. Step 6: Final answer
   x = 97.00