Finding the Third Proportional to 666.56 and 666.56

Step by Step Solution

1. Step 1: Write the proportion equation
   666.56 : 666.56 = 666.56 : x
2. Step 2: Convert to fraction form
   666.56/666.56 = 666.56/x
3. Step 3: Cross multiply
   666.56x = 666.56 × 666.56
4. Step 4: Simplify right side
   666.56x = 444,305.57
5. Step 5: Solve for x
   x = 444,305.57/666.56
6. Step 6: Final answer
   x = 666.56