Finding the Third Proportional to 364.78 and 418.78

Step by Step Solution

1. Step 1: Write the proportion equation
   364.78 : 418.78 = 418.78 : x
2. Step 2: Convert to fraction form
   364.78/418.78 = 418.78/x
3. Step 3: Cross multiply
   364.78x = 418.78 × 418.78
4. Step 4: Simplify right side
   364.78x = 175,377.74
5. Step 5: Solve for x
   x = 175,377.74/364.78
6. Step 6: Final answer
   x = 480.78