Finding the Third Proportional to 170,394 and 257,978

Step by Step Solution

1. Step 1: Write the proportion equation
   170,394 : 257,978 = 257,978 : x
2. Step 2: Convert to fraction form
   170,394/257,978 = 257,978/x
3. Step 3: Cross multiply
   170,394x = 257,978 × 257,978
4. Step 4: Simplify right side
   170,394x = 66,552,648,484
5. Step 5: Solve for x
   x = 66,552,648,484/170,394
6. Step 6: Final answer
   x = 390,580.94