Finding the Fourth Proportional to 111.54, 153.82 and 72.13

Step by Step Solution

1. Step 1: Write the proportion equation
   111.54 : 153.82 = 72.13 : x
2. Step 2: Convert to fraction form
   111.54/153.82 = 72.13/x
3. Step 3: Cross multiply
   111.54x = 153.82 × 72.13
4. Step 4: Simplify right side
   111.54x = 11,095.04
5. Step 5: Solve for x
   x = 11,095.04/111.54
6. Step 6: Final answer
   x = 99.47