Finding the Fourth Proportional to 105.57, 158.42 and 51.43

Step by Step Solution

1. Step 1: Write the proportion equation
   105.57 : 158.42 = 51.43 : x
2. Step 2: Convert to fraction form
   105.57/158.42 = 51.43/x
3. Step 3: Cross multiply
   105.57x = 158.42 × 51.43
4. Step 4: Simplify right side
   105.57x = 8,147.90
5. Step 5: Solve for x
   x = 8,147.90/105.57
6. Step 6: Final answer
   x = 77.18