Finding the Third Proportional to 208,930 and 318,290

Step by Step Solution

1. Step 1: Write the proportion equation
   208,930 : 318,290 = 318,290 : x
2. Step 2: Convert to fraction form
   208,930/318,290 = 318,290/x
3. Step 3: Cross multiply
   208,930x = 318,290 × 318,290
4. Step 4: Simplify right side
   208,930x = 101,308,524,100
5. Step 5: Solve for x
   x = 101,308,524,100/208,930
6. Step 6: Final answer
   x = 484,892.18