Finding the Fourth Proportional to 105.94, 158.60 and 90.52

Step by Step Solution

1. Step 1: Write the proportion equation
   105.94 : 158.60 = 90.52 : x
2. Step 2: Convert to fraction form
   105.94/158.60 = 90.52/x
3. Step 3: Cross multiply
   105.94x = 158.60 × 90.52
4. Step 4: Simplify right side
   105.94x = 14,356.47
5. Step 5: Solve for x
   x = 14,356.47/105.94
6. Step 6: Final answer
   x = 135.52