Finding the Third Proportional to 123,018.75 and 261,346.50

Step by Step Solution

1. Step 1: Write the proportion equation
   123,018.75 : 261,346.50 = 261,346.50 : x
2. Step 2: Convert to fraction form
   123,018.75/261,346.50 = 261,346.50/x
3. Step 3: Cross multiply
   123,018.75x = 261,346.50 × 261,346.50
4. Step 4: Simplify right side
   123,018.75x = 68,301,993,062.25
5. Step 5: Solve for x
   x = 68,301,993,062.25/123,018.75
6. Step 6: Final answer
   x = 555,216.12