Finding the Third Proportional to 321,781.50 and 423,142.25

Step by Step Solution

1. Step 1: Write the proportion equation
   321,781.50 : 423,142.25 = 423,142.25 : x
2. Step 2: Convert to fraction form
   321,781.50/423,142.25 = 423,142.25/x
3. Step 3: Cross multiply
   321,781.50x = 423,142.25 × 423,142.25
4. Step 4: Simplify right side
   321,781.50x = 179,049,363,735.06
5. Step 5: Solve for x
   x = 179,049,363,735.06/321,781.50
6. Step 6: Final answer
   x = 556,431.50