Finding the Third Proportional to 172,400 and 264,900

Step by Step Solution

1. Step 1: Write the proportion equation
   172,400 : 264,900 = 264,900 : x
2. Step 2: Convert to fraction form
   172,400/264,900 = 264,900/x
3. Step 3: Cross multiply
   172,400x = 264,900 × 264,900
4. Step 4: Simplify right side
   172,400x = 70,172,010,000
5. Step 5: Solve for x
   x = 70,172,010,000/172,400
6. Step 6: Final answer
   x = 407,030.22