Finding the Fourth Proportional to 105.45, 158.18 and 28.42

Step by Step Solution

1. Step 1: Write the proportion equation
   105.45 : 158.18 = 28.42 : x
2. Step 2: Convert to fraction form
   105.45/158.18 = 28.42/x
3. Step 3: Cross multiply
   105.45x = 158.18 × 28.42
4. Step 4: Simplify right side
   105.45x = 4,495.48
5. Step 5: Solve for x
   x = 4,495.48/105.45
6. Step 6: Final answer
   x = 42.63