Finding the Third Proportional to 4,707,840 and 9,980,716

Step by Step Solution

1. Step 1: Write the proportion equation
   4,707,840 : 9,980,716 = 9,980,716 : x
2. Step 2: Convert to fraction form
   4,707,840/9,980,716 = 9,980,716/x
3. Step 3: Cross multiply
   4,707,840x = 9,980,716 × 9,980,716
4. Step 4: Simplify right side
   4,707,840x = 99,614,691,872,656
5. Step 5: Solve for x
   x = 99,614,691,872,656/4,707,840
6. Step 6: Final answer
   x = 21,159,319.75