Finding the Third Proportional to 139,428 and 209,460

Step by Step Solution

1. Step 1: Write the proportion equation
   139,428 : 209,460 = 209,460 : x
2. Step 2: Convert to fraction form
   139,428/209,460 = 209,460/x
3. Step 3: Cross multiply
   139,428x = 209,460 × 209,460
4. Step 4: Simplify right side
   139,428x = 43,873,491,600
5. Step 5: Solve for x
   x = 43,873,491,600/139,428
6. Step 6: Final answer
   x = 314,667.73