Finding the Third Proportional to 663.56 and 928.78

Step by Step Solution

1. Step 1: Write the proportion equation
   663.56 : 928.78 = 928.78 : x
2. Step 2: Convert to fraction form
   663.56/928.78 = 928.78/x
3. Step 3: Cross multiply
   663.56x = 928.78 × 928.78
4. Step 4: Simplify right side
   663.56x = 862,634.61
5. Step 5: Solve for x
   x = 862,634.61/663.56
6. Step 6: Final answer
   x = 1,300.01