Finding the Third Proportional to 1,263,778 and 1,639,488

Step by Step Solution

1. Step 1: Write the proportion equation
   1,263,778 : 1,639,488 = 1,639,488 : x
2. Step 2: Convert to fraction form
   1,263,778/1,639,488 = 1,639,488/x
3. Step 3: Cross multiply
   1,263,778x = 1,639,488 × 1,639,488
4. Step 4: Simplify right side
   1,263,778x = 2,687,920,902,144
5. Step 5: Solve for x
   x = 2,687,920,902,144/1,263,778
6. Step 6: Final answer
   x = 2,126,893.25