Finding the Third Proportional to 5,215,914 and 7,978,797

Step by Step Solution

1. Step 1: Write the proportion equation
   5,215,914 : 7,978,797 = 7,978,797 : x
2. Step 2: Convert to fraction form
   5,215,914/7,978,797 = 7,978,797/x
3. Step 3: Cross multiply
   5,215,914x = 7,978,797 × 7,978,797
4. Step 4: Simplify right side
   5,215,914x = 63,661,201,567,209
5. Step 5: Solve for x
   x = 63,661,201,567,209/5,215,914
6. Step 6: Final answer
   x = 12,205,186.20