Finding the Third Proportional to 156,978 and 339,856

Step by Step Solution

1. Step 1: Write the proportion equation
   156,978 : 339,856 = 339,856 : x
2. Step 2: Convert to fraction form
   156,978/339,856 = 339,856/x
3. Step 3: Cross multiply
   156,978x = 339,856 × 339,856
4. Step 4: Simplify right side
   156,978x = 115,502,100,736
5. Step 5: Solve for x
   x = 115,502,100,736/156,978
6. Step 6: Final answer
   x = 735,785.27