Finding the Third Proportional to 31,509 and 67,189.50

Step by Step Solution

1. Step 1: Write the proportion equation
   31,509 : 67,189.50 = 67,189.50 : x
2. Step 2: Convert to fraction form
   31,509/67,189.50 = 67,189.50/x
3. Step 3: Cross multiply
   31,509x = 67,189.50 × 67,189.50
4. Step 4: Simplify right side
   31,509x = 4,514,428,910.25
5. Step 5: Solve for x
   x = 4,514,428,910.25/31,509
6. Step 6: Final answer
   x = 143,274.27