Finding the Third Proportional to 639,891 and 1,400,310

Step by Step Solution

1. Step 1: Write the proportion equation
   639,891 : 1,400,310 = 1,400,310 : x
2. Step 2: Convert to fraction form
   639,891/1,400,310 = 1,400,310/x
3. Step 3: Cross multiply
   639,891x = 1,400,310 × 1,400,310
4. Step 4: Simplify right side
   639,891x = 1,960,868,096,100
5. Step 5: Solve for x
   x = 1,960,868,096,100/639,891
6. Step 6: Final answer
   x = 3,064,378.30