Finding the Third Proportional to 5,429,918 and 7,978,664

Step by Step Solution

1. Step 1: Write the proportion equation
   5,429,918 : 7,978,664 = 7,978,664 : x
2. Step 2: Convert to fraction form
   5,429,918/7,978,664 = 7,978,664/x
3. Step 3: Cross multiply
   5,429,918x = 7,978,664 × 7,978,664
4. Step 4: Simplify right side
   5,429,918x = 63,659,079,224,896
5. Step 5: Solve for x
   x = 63,659,079,224,896/5,429,918
6. Step 6: Final answer
   x = 11,723,764.38