Finding the Third Proportional to 148,992 and 321,216

Step by Step Solution

1. Step 1: Write the proportion equation
   148,992 : 321,216 = 321,216 : x
2. Step 2: Convert to fraction form
   148,992/321,216 = 321,216/x
3. Step 3: Cross multiply
   148,992x = 321,216 × 321,216
4. Step 4: Simplify right side
   148,992x = 103,179,718,656
5. Step 5: Solve for x
   x = 103,179,718,656/148,992
6. Step 6: Final answer
   x = 692,518.52