Finding the Third Proportional to 2,666.50 and 3,128.50

Step by Step Solution

1. Step 1: Write the proportion equation
   2,666.50 : 3,128.50 = 3,128.50 : x
2. Step 2: Convert to fraction form
   2,666.50/3,128.50 = 3,128.50/x
3. Step 3: Cross multiply
   2,666.50x = 3,128.50 × 3,128.50
4. Step 4: Simplify right side
   2,666.50x = 9,787,512.25
5. Step 5: Solve for x
   x = 9,787,512.25/2,666.50
6. Step 6: Final answer
   x = 3,670.55