Finding the Third Proportional to 1,311,207 and 1,978,857

Step by Step Solution

1. Step 1: Write the proportion equation
   1,311,207 : 1,978,857 = 1,978,857 : x
2. Step 2: Convert to fraction form
   1,311,207/1,978,857 = 1,978,857/x
3. Step 3: Cross multiply
   1,311,207x = 1,978,857 × 1,978,857
4. Step 4: Simplify right side
   1,311,207x = 3,915,875,026,449
5. Step 5: Solve for x
   x = 3,915,875,026,449/1,311,207
6. Step 6: Final answer
   x = 2,986,465.93