Finding the Fourth Proportional to 105.26, 145.32 and 72.69

Step by Step Solution

1. Step 1: Write the proportion equation
   105.26 : 145.32 = 72.69 : x
2. Step 2: Convert to fraction form
   105.26/145.32 = 72.69/x
3. Step 3: Cross multiply
   105.26x = 145.32 × 72.69
4. Step 4: Simplify right side
   105.26x = 10,563.31
5. Step 5: Solve for x
   x = 10,563.31/105.26
6. Step 6: Final answer
   x = 100.35