Finding the Third Proportional to 209,830 and 316,500

Step by Step Solution

1. Step 1: Write the proportion equation
   209,830 : 316,500 = 316,500 : x
2. Step 2: Convert to fraction form
   209,830/316,500 = 316,500/x
3. Step 3: Cross multiply
   209,830x = 316,500 × 316,500
4. Step 4: Simplify right side
   209,830x = 100,172,250,000
5. Step 5: Solve for x
   x = 100,172,250,000/209,830
6. Step 6: Final answer
   x = 477,397.18