Finding the Fourth Proportional to 105.78, 158.50 and 60.10

Step by Step Solution

1. Step 1: Write the proportion equation
   105.78 : 158.50 = 60.10 : x
2. Step 2: Convert to fraction form
   105.78/158.50 = 60.10/x
3. Step 3: Cross multiply
   105.78x = 158.50 × 60.10
4. Step 4: Simplify right side
   105.78x = 9,525.85
5. Step 5: Solve for x
   x = 9,525.85/105.78
6. Step 6: Final answer
   x = 90.05