Finding the Third Proportional to 31,711.50 and 81,921.38

Step by Step Solution

1. Step 1: Write the proportion equation
   31,711.50 : 81,921.38 = 81,921.38 : x
2. Step 2: Convert to fraction form
   31,711.50/81,921.38 = 81,921.38/x
3. Step 3: Cross multiply
   31,711.50x = 81,921.38 × 81,921.38
4. Step 4: Simplify right side
   31,711.50x = 6,711,111,681.89
5. Step 5: Solve for x
   x = 6,711,111,681.89/31,711.50
6. Step 6: Final answer
   x = 211,630.22