Finding the Third Proportional to 216,420 and 323,418.63

Step by Step Solution

1. Step 1: Write the proportion equation
   216,420 : 323,418.63 = 323,418.63 : x
2. Step 2: Convert to fraction form
   216,420/323,418.63 = 323,418.63/x
3. Step 3: Cross multiply
   216,420x = 323,418.63 × 323,418.63
4. Step 4: Simplify right side
   216,420x = 104,599,606,996.89
5. Step 5: Solve for x
   x = 104,599,606,996.89/216,420
6. Step 6: Final answer
   x = 483,317.66