Finding the Fourth Proportional to 105.59, 145.59 and 72.41

Step by Step Solution

1. Step 1: Write the proportion equation
   105.59 : 145.59 = 72.41 : x
2. Step 2: Convert to fraction form
   105.59/145.59 = 72.41/x
3. Step 3: Cross multiply
   105.59x = 145.59 × 72.41
4. Step 4: Simplify right side
   105.59x = 10,541.44
5. Step 5: Solve for x
   x = 10,541.44/105.59
6. Step 6: Final answer
   x = 99.84