Finding the Fourth Proportional to 117.89, 176.86 and 72.18

Step by Step Solution

1. Step 1: Write the proportion equation
   117.89 : 176.86 = 72.18 : x
2. Step 2: Convert to fraction form
   117.89/176.86 = 72.18/x
3. Step 3: Cross multiply
   117.89x = 176.86 × 72.18
4. Step 4: Simplify right side
   117.89x = 12,765.39
5. Step 5: Solve for x
   x = 12,765.39/117.89
6. Step 6: Final answer
   x = 108.28