Finding the Third Proportional to 5,578,380 and 8,613,621

Step by Step Solution

1. Step 1: Write the proportion equation
   5,578,380 : 8,613,621 = 8,613,621 : x
2. Step 2: Convert to fraction form
   5,578,380/8,613,621 = 8,613,621/x
3. Step 3: Cross multiply
   5,578,380x = 8,613,621 × 8,613,621
4. Step 4: Simplify right side
   5,578,380x = 74,194,466,731,641
5. Step 5: Solve for x
   x = 74,194,466,731,641/5,578,380
6. Step 6: Final answer
   x = 13,300,360.81