Finding the Fourth Proportional to 121.94, 168.31 and 72.82

Step by Step Solution

1. Step 1: Write the proportion equation
   121.94 : 168.31 = 72.82 : x
2. Step 2: Convert to fraction form
   121.94/168.31 = 72.82/x
3. Step 3: Cross multiply
   121.94x = 168.31 × 72.82
4. Step 4: Simplify right side
   121.94x = 12,256.33
5. Step 5: Solve for x
   x = 12,256.33/121.94
6. Step 6: Final answer
   x = 100.51