Finding the Fourth Proportional to 105.59, 158.40 and 28.55

Step by Step Solution

1. Step 1: Write the proportion equation
   105.59 : 158.40 = 28.55 : x
2. Step 2: Convert to fraction form
   105.59/158.40 = 28.55/x
3. Step 3: Cross multiply
   105.59x = 158.40 × 28.55
4. Step 4: Simplify right side
   105.59x = 4,522.72
5. Step 5: Solve for x
   x = 4,522.72/105.59
6. Step 6: Final answer
   x = 42.83