Finding the Fourth Proportional to 123.91, 185.79 and 72.56

Step by Step Solution

1. Step 1: Write the proportion equation
   123.91 : 185.79 = 72.56 : x
2. Step 2: Convert to fraction form
   123.91/185.79 = 72.56/x
3. Step 3: Cross multiply
   123.91x = 185.79 × 72.56
4. Step 4: Simplify right side
   123.91x = 13,481.39
5. Step 5: Solve for x
   x = 13,481.39/123.91
6. Step 6: Final answer
   x = 108.80