Finding the Third Proportional to 256,630.78 and 558,414

Step by Step Solution

1. Step 1: Write the proportion equation
   256,630.78 : 558,414 = 558,414 : x
2. Step 2: Convert to fraction form
   256,630.78/558,414 = 558,414/x
3. Step 3: Cross multiply
   256,630.78x = 558,414 × 558,414
4. Step 4: Simplify right side
   256,630.78x = 311,826,195,396
5. Step 5: Solve for x
   x = 311,826,195,396/256,630.78
6. Step 6: Final answer
   x = 1,215,077.14