Finding the Third Proportional to 275,868 and 421,820.72

Step by Step Solution

1. Step 1: Write the proportion equation
   275,868 : 421,820.72 = 421,820.72 : x
2. Step 2: Convert to fraction form
   275,868/421,820.72 = 421,820.72/x
3. Step 3: Cross multiply
   275,868x = 421,820.72 × 421,820.72
4. Step 4: Simplify right side
   275,868x = 177,932,718,766.77
5. Step 5: Solve for x
   x = 177,932,718,766.77/275,868
6. Step 6: Final answer
   x = 644,992.24