Finding the Third Proportional to 418.78 and 1,012.78

Step by Step Solution

1. Step 1: Write the proportion equation
   418.78 : 1,012.78 = 1,012.78 : x
2. Step 2: Convert to fraction form
   418.78/1,012.78 = 1,012.78/x
3. Step 3: Cross multiply
   418.78x = 1,012.78 × 1,012.78
4. Step 4: Simplify right side
   418.78x = 1,025,725.86
5. Step 5: Solve for x
   x = 1,025,725.86/418.78
6. Step 6: Final answer
   x = 2,449.31