Finding the Fourth Proportional to 111.85, 154.31 and 72.50

Step by Step Solution

1. Step 1: Write the proportion equation
   111.85 : 154.31 = 72.50 : x
2. Step 2: Convert to fraction form
   111.85/154.31 = 72.50/x
3. Step 3: Cross multiply
   111.85x = 154.31 × 72.50
4. Step 4: Simplify right side
   111.85x = 11,186.34
5. Step 5: Solve for x
   x = 11,186.34/111.85
6. Step 6: Final answer
   x = 100.01