Finding the Fourth Proportional to 111.50, 153.92 and 72.71

Step by Step Solution

1. Step 1: Write the proportion equation
   111.50 : 153.92 = 72.71 : x
2. Step 2: Convert to fraction form
   111.50/153.92 = 72.71/x
3. Step 3: Cross multiply
   111.50x = 153.92 × 72.71
4. Step 4: Simplify right side
   111.50x = 11,191.16
5. Step 5: Solve for x
   x = 11,191.16/111.50
6. Step 6: Final answer
   x = 100.37