Finding the Third Proportional to 31,426 and 68,390

Step by Step Solution

1. Step 1: Write the proportion equation
   31,426 : 68,390 = 68,390 : x
2. Step 2: Convert to fraction form
   31,426/68,390 = 68,390/x
3. Step 3: Cross multiply
   31,426x = 68,390 × 68,390
4. Step 4: Simplify right side
   31,426x = 4,677,192,100
5. Step 5: Solve for x
   x = 4,677,192,100/31,426
6. Step 6: Final answer
   x = 148,831.93