Finding the Third Proportional to 256,090.50 and 557,581.50

Step by Step Solution

1. Step 1: Write the proportion equation
   256,090.50 : 557,581.50 = 557,581.50 : x
2. Step 2: Convert to fraction form
   256,090.50/557,581.50 = 557,581.50/x
3. Step 3: Cross multiply
   256,090.50x = 557,581.50 × 557,581.50
4. Step 4: Simplify right side
   256,090.50x = 310,897,129,142.25
5. Step 5: Solve for x
   x = 310,897,129,142.25/256,090.50
6. Step 6: Final answer
   x = 1,214,012.74