Finding the Fourth Proportional to 72.09, 108.72 and 65.58

Step by Step Solution

1. Step 1: Write the proportion equation
   72.09 : 108.72 = 65.58 : x
2. Step 2: Convert to fraction form
   72.09/108.72 = 65.58/x
3. Step 3: Cross multiply
   72.09x = 108.72 × 65.58
4. Step 4: Simplify right side
   72.09x = 7,129.86
5. Step 5: Solve for x
   x = 7,129.86/72.09
6. Step 6: Final answer
   x = 98.90