Finding the Third Proportional to 256,493 and 556,456

Step by Step Solution

1. Step 1: Write the proportion equation
   256,493 : 556,456 = 556,456 : x
2. Step 2: Convert to fraction form
   256,493/556,456 = 556,456/x
3. Step 3: Cross multiply
   256,493x = 556,456 × 556,456
4. Step 4: Simplify right side
   256,493x = 309,643,279,936
5. Step 5: Solve for x
   x = 309,643,279,936/256,493
6. Step 6: Final answer
   x = 1,207,219.22