Finding the Third Proportional to 123,216 and 259,312

Step by Step Solution

1. Step 1: Write the proportion equation
   123,216 : 259,312 = 259,312 : x
2. Step 2: Convert to fraction form
   123,216/259,312 = 259,312/x
3. Step 3: Cross multiply
   123,216x = 259,312 × 259,312
4. Step 4: Simplify right side
   123,216x = 67,242,713,344
5. Step 5: Solve for x
   x = 67,242,713,344/123,216
6. Step 6: Final answer
   x = 545,730.37