Finding the Third Proportional to 639,776 and 1,358,272

Step by Step Solution

1. Step 1: Write the proportion equation
   639,776 : 1,358,272 = 1,358,272 : x
2. Step 2: Convert to fraction form
   639,776/1,358,272 = 1,358,272/x
3. Step 3: Cross multiply
   639,776x = 1,358,272 × 1,358,272
4. Step 4: Simplify right side
   639,776x = 1,844,902,825,984
5. Step 5: Solve for x
   x = 1,844,902,825,984/639,776
6. Step 6: Final answer
   x = 2,883,669.95