Finding the Third Proportional to 669.56 and 1,439.72

Step by Step Solution

1. Step 1: Write the proportion equation
   669.56 : 1,439.72 = 1,439.72 : x
2. Step 2: Convert to fraction form
   669.56/1,439.72 = 1,439.72/x
3. Step 3: Cross multiply
   669.56x = 1,439.72 × 1,439.72
4. Step 4: Simplify right side
   669.56x = 2,072,790.08
5. Step 5: Solve for x
   x = 2,072,790.08/669.56
6. Step 6: Final answer
   x = 3,095.74