Finding the Third Proportional to 257,656 and 385,300

Step by Step Solution

1. Step 1: Write the proportion equation
   257,656 : 385,300 = 385,300 : x
2. Step 2: Convert to fraction form
   257,656/385,300 = 385,300/x
3. Step 3: Cross multiply
   257,656x = 385,300 × 385,300
4. Step 4: Simplify right side
   257,656x = 148,456,090,000
5. Step 5: Solve for x
   x = 148,456,090,000/257,656
6. Step 6: Final answer
   x = 576,179.44