Finding the Third Proportional to 256,218 and 385,150

Step by Step Solution

1. Step 1: Write the proportion equation
   256,218 : 385,150 = 385,150 : x
2. Step 2: Convert to fraction form
   256,218/385,150 = 385,150/x
3. Step 3: Cross multiply
   256,218x = 385,150 × 385,150
4. Step 4: Simplify right side
   256,218x = 148,340,522,500
5. Step 5: Solve for x
   x = 148,340,522,500/256,218
6. Step 6: Final answer
   x = 578,962.14