Finding the Fourth Proportional to 104.94, 144.78 and 72.18

Step by Step Solution

1. Step 1: Write the proportion equation
   104.94 : 144.78 = 72.18 : x
2. Step 2: Convert to fraction form
   104.94/144.78 = 72.18/x
3. Step 3: Cross multiply
   104.94x = 144.78 × 72.18
4. Step 4: Simplify right side
   104.94x = 10,450.22
5. Step 5: Solve for x
   x = 10,450.22/104.94
6. Step 6: Final answer
   x = 99.58