Finding the Third Proportional to 643,460 and 1,386,650

Step by Step Solution

1. Step 1: Write the proportion equation
   643,460 : 1,386,650 = 1,386,650 : x
2. Step 2: Convert to fraction form
   643,460/1,386,650 = 1,386,650/x
3. Step 3: Cross multiply
   643,460x = 1,386,650 × 1,386,650
4. Step 4: Simplify right side
   643,460x = 1,922,798,222,500
5. Step 5: Solve for x
   x = 1,922,798,222,500/643,460
6. Step 6: Final answer
   x = 2,988,217.17