Finding the Third Proportional to 811,440 and 1,261,409

Step by Step Solution

1. Step 1: Write the proportion equation
   811,440 : 1,261,409 = 1,261,409 : x
2. Step 2: Convert to fraction form
   811,440/1,261,409 = 1,261,409/x
3. Step 3: Cross multiply
   811,440x = 1,261,409 × 1,261,409
4. Step 4: Simplify right side
   811,440x = 1,591,152,665,281
5. Step 5: Solve for x
   x = 1,591,152,665,281/811,440
6. Step 6: Final answer
   x = 1,960,899.96