Finding the Fourth Proportional to 105.56, 145.55 and 74.58

Step by Step Solution

1. Step 1: Write the proportion equation
   105.56 : 145.55 = 74.58 : x
2. Step 2: Convert to fraction form
   105.56/145.55 = 74.58/x
3. Step 3: Cross multiply
   105.56x = 145.55 × 74.58
4. Step 4: Simplify right side
   105.56x = 10,855.31
5. Step 5: Solve for x
   x = 10,855.31/105.56
6. Step 6: Final answer
   x = 102.83