Finding the Fourth Proportional to 105.22, 145.25 and 72.51

Step by Step Solution

1. Step 1: Write the proportion equation
   105.22 : 145.25 = 72.51 : x
2. Step 2: Convert to fraction form
   105.22/145.25 = 72.51/x
3. Step 3: Cross multiply
   105.22x = 145.25 × 72.51
4. Step 4: Simplify right side
   105.22x = 10,532.08
5. Step 5: Solve for x
   x = 10,532.08/105.22
6. Step 6: Final answer
   x = 100.10