Finding the Third Proportional to 31,720.50 and 67,815

Step by Step Solution

1. Step 1: Write the proportion equation
   31,720.50 : 67,815 = 67,815 : x
2. Step 2: Convert to fraction form
   31,720.50/67,815 = 67,815/x
3. Step 3: Cross multiply
   31,720.50x = 67,815 × 67,815
4. Step 4: Simplify right side
   31,720.50x = 4,598,874,225
5. Step 5: Solve for x
   x = 4,598,874,225/31,720.50
6. Step 6: Final answer
   x = 144,981.14