Finding the Third Proportional to 257,809.50 and 378,810

Step by Step Solution

1. Step 1: Write the proportion equation
   257,809.50 : 378,810 = 378,810 : x
2. Step 2: Convert to fraction form
   257,809.50/378,810 = 378,810/x
3. Step 3: Cross multiply
   257,809.50x = 378,810 × 378,810
4. Step 4: Simplify right side
   257,809.50x = 143,497,016,100
5. Step 5: Solve for x
   x = 143,497,016,100/257,809.50
6. Step 6: Final answer
   x = 556,600.96