Finding the Fourth Proportional to 111.29, 153.43 and 71.88

Step by Step Solution

1. Step 1: Write the proportion equation
   111.29 : 153.43 = 71.88 : x
2. Step 2: Convert to fraction form
   111.29/153.43 = 71.88/x
3. Step 3: Cross multiply
   111.29x = 153.43 × 71.88
4. Step 4: Simplify right side
   111.29x = 11,028.55
5. Step 5: Solve for x
   x = 11,028.55/111.29
6. Step 6: Final answer
   x = 99.10