Finding the Third Proportional to 1,605.66 and 2,128.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,605.66 : 2,128.78 = 2,128.78 : x
2. Step 2: Convert to fraction form
   1,605.66/2,128.78 = 2,128.78/x
3. Step 3: Cross multiply
   1,605.66x = 2,128.78 × 2,128.78
4. Step 4: Simplify right side
   1,605.66x = 4,531,709.61
5. Step 5: Solve for x
   x = 4,531,709.61/1,605.66
6. Step 6: Final answer
   x = 2,822.34