Finding the Third Proportional to 1,215,988 and 2,639,660

Step by Step Solution

1. Step 1: Write the proportion equation
   1,215,988 : 2,639,660 = 2,639,660 : x
2. Step 2: Convert to fraction form
   1,215,988/2,639,660 = 2,639,660/x
3. Step 3: Cross multiply
   1,215,988x = 2,639,660 × 2,639,660
4. Step 4: Simplify right side
   1,215,988x = 6,967,804,915,600
5. Step 5: Solve for x
   x = 6,967,804,915,600/1,215,988
6. Step 6: Final answer
   x = 5,730,159.27