Finding the Third Proportional to 31,391 and 67,102

Step by Step Solution

1. Step 1: Write the proportion equation
   31,391 : 67,102 = 67,102 : x
2. Step 2: Convert to fraction form
   31,391/67,102 = 67,102/x
3. Step 3: Cross multiply
   31,391x = 67,102 × 67,102
4. Step 4: Simplify right side
   31,391x = 4,502,678,404
5. Step 5: Solve for x
   x = 4,502,678,404/31,391
6. Step 6: Final answer
   x = 143,438.51