Finding the Fourth Proportional to 72.89, 108.35 and 71.68

Step by Step Solution

1. Step 1: Write the proportion equation
   72.89 : 108.35 = 71.68 : x
2. Step 2: Convert to fraction form
   72.89/108.35 = 71.68/x
3. Step 3: Cross multiply
   72.89x = 108.35 × 71.68
4. Step 4: Simplify right side
   72.89x = 7,766.53
5. Step 5: Solve for x
   x = 7,766.53/72.89
6. Step 6: Final answer
   x = 106.55