Finding the Fourth Proportional to 111.77, 153.33 and 104.78

Step by Step Solution

1. Step 1: Write the proportion equation
   111.77 : 153.33 = 104.78 : x
2. Step 2: Convert to fraction form
   111.77/153.33 = 104.78/x
3. Step 3: Cross multiply
   111.77x = 153.33 × 104.78
4. Step 4: Simplify right side
   111.77x = 16,065.15
5. Step 5: Solve for x
   x = 16,065.15/111.77
6. Step 6: Final answer
   x = 143.74