Finding the Third Proportional to 221,990 and 488,172

Step by Step Solution

1. Step 1: Write the proportion equation
   221,990 : 488,172 = 488,172 : x
2. Step 2: Convert to fraction form
   221,990/488,172 = 488,172/x
3. Step 3: Cross multiply
   221,990x = 488,172 × 488,172
4. Step 4: Simplify right side
   221,990x = 238,311,901,584
5. Step 5: Solve for x
   x = 238,311,901,584/221,990
6. Step 6: Final answer
   x = 1,073,525.39