Finding the Third Proportional to 139,156 and 209,374

Step by Step Solution

1. Step 1: Write the proportion equation
   139,156 : 209,374 = 209,374 : x
2. Step 2: Convert to fraction form
   139,156/209,374 = 209,374/x
3. Step 3: Cross multiply
   139,156x = 209,374 × 209,374
4. Step 4: Simplify right side
   139,156x = 43,837,471,876
5. Step 5: Solve for x
   x = 43,837,471,876/139,156
6. Step 6: Final answer
   x = 315,023.94