Finding the Third Proportional to 85,599 and 206,215.50

Step by Step Solution

1. Step 1: Write the proportion equation
   85,599 : 206,215.50 = 206,215.50 : x
2. Step 2: Convert to fraction form
   85,599/206,215.50 = 206,215.50/x
3. Step 3: Cross multiply
   85,599x = 206,215.50 × 206,215.50
4. Step 4: Simplify right side
   85,599x = 42,524,832,440.25
5. Step 5: Solve for x
   x = 42,524,832,440.25/85,599
6. Step 6: Final answer
   x = 496,791.23