Finding the Third Proportional to 669 and 1,435.50

Step by Step Solution

1. Step 1: Write the proportion equation
   669 : 1,435.50 = 1,435.50 : x
2. Step 2: Convert to fraction form
   669/1,435.50 = 1,435.50/x
3. Step 3: Cross multiply
   669x = 1,435.50 × 1,435.50
4. Step 4: Simplify right side
   669x = 2,060,660.25
5. Step 5: Solve for x
   x = 2,060,660.25/669
6. Step 6: Final answer
   x = 3,080.21