Finding the Fourth Proportional to 124.61, 171.98 and 72.17

Step by Step Solution

1. Step 1: Write the proportion equation
   124.61 : 171.98 = 72.17 : x
2. Step 2: Convert to fraction form
   124.61/171.98 = 72.17/x
3. Step 3: Cross multiply
   124.61x = 171.98 × 72.17
4. Step 4: Simplify right side
   124.61x = 12,410.85
5. Step 5: Solve for x
   x = 12,410.85/124.61
6. Step 6: Final answer
   x = 99.60