Finding the Fourth Proportional to 404.35, 606.42 and 111.78

Step by Step Solution

1. Step 1: Write the proportion equation
   404.35 : 606.42 = 111.78 : x
2. Step 2: Convert to fraction form
   404.35/606.42 = 111.78/x
3. Step 3: Cross multiply
   404.35x = 606.42 × 111.78
4. Step 4: Simplify right side
   404.35x = 67,786.35
5. Step 5: Solve for x
   x = 67,786.35/404.35
6. Step 6: Final answer
   x = 167.64