Finding the Fourth Proportional to 123.88, 185.55 and 72.45

Step by Step Solution

1. Step 1: Write the proportion equation
   123.88 : 185.55 = 72.45 : x
2. Step 2: Convert to fraction form
   123.88/185.55 = 72.45/x
3. Step 3: Cross multiply
   123.88x = 185.55 × 72.45
4. Step 4: Simplify right side
   123.88x = 13,443.10
5. Step 5: Solve for x
   x = 13,443.10/123.88
6. Step 6: Final answer
   x = 108.52