Finding the Fourth Proportional to 111.12, 153.28 and 71.76

Step by Step Solution

1. Step 1: Write the proportion equation
   111.12 : 153.28 = 71.76 : x
2. Step 2: Convert to fraction form
   111.12/153.28 = 71.76/x
3. Step 3: Cross multiply
   111.12x = 153.28 × 71.76
4. Step 4: Simplify right side
   111.12x = 10,999.37
5. Step 5: Solve for x
   x = 10,999.37/111.12
6. Step 6: Final answer
   x = 98.99