Finding the Fourth Proportional to 105.27, 145.08 and 72.47

Step by Step Solution

1. Step 1: Write the proportion equation
   105.27 : 145.08 = 72.47 : x
2. Step 2: Convert to fraction form
   105.27/145.08 = 72.47/x
3. Step 3: Cross multiply
   105.27x = 145.08 × 72.47
4. Step 4: Simplify right side
   105.27x = 10,513.22
5. Step 5: Solve for x
   x = 10,513.22/105.27
6. Step 6: Final answer
   x = 99.87