Finding the Third Proportional to 5,215,600 and 7,978,417

Step by Step Solution

1. Step 1: Write the proportion equation
   5,215,600 : 7,978,417 = 7,978,417 : x
2. Step 2: Convert to fraction form
   5,215,600/7,978,417 = 7,978,417/x
3. Step 3: Cross multiply
   5,215,600x = 7,978,417 × 7,978,417
4. Step 4: Simplify right side
   5,215,600x = 63,655,137,825,889
5. Step 5: Solve for x
   x = 63,655,137,825,889/5,215,600
6. Step 6: Final answer
   x = 12,204,758.38