Finding the Third Proportional to 990,978 and 2,171,280

Step by Step Solution

1. Step 1: Write the proportion equation
   990,978 : 2,171,280 = 2,171,280 : x
2. Step 2: Convert to fraction form
   990,978/2,171,280 = 2,171,280/x
3. Step 3: Cross multiply
   990,978x = 2,171,280 × 2,171,280
4. Step 4: Simplify right side
   990,978x = 4,714,456,838,400
5. Step 5: Solve for x
   x = 4,714,456,838,400/990,978
6. Step 6: Final answer
   x = 4,757,377.90