Finding the Fourth Proportional to 105.29, 145.42 and 74.28

Step by Step Solution

1. Step 1: Write the proportion equation
   105.29 : 145.42 = 74.28 : x
2. Step 2: Convert to fraction form
   105.29/145.42 = 74.28/x
3. Step 3: Cross multiply
   105.29x = 145.42 × 74.28
4. Step 4: Simplify right side
   105.29x = 10,801.61
5. Step 5: Solve for x
   x = 10,801.61/105.29
6. Step 6: Final answer
   x = 102.59