Finding the Third Proportional to 185.20 and 400.78

Step by Step Solution

1. Step 1: Write the proportion equation
   185.20 : 400.78 = 400.78 : x
2. Step 2: Convert to fraction form
   185.20/400.78 = 400.78/x
3. Step 3: Cross multiply
   185.20x = 400.78 × 400.78
4. Step 4: Simplify right side
   185.20x = 160,625.61
5. Step 5: Solve for x
   x = 160,625.61/185.20
6. Step 6: Final answer
   x = 867.29