Finding the Third Proportional to 31,430 and 67,072

Step by Step Solution

1. Step 1: Write the proportion equation
   31,430 : 67,072 = 67,072 : x
2. Step 2: Convert to fraction form
   31,430/67,072 = 67,072/x
3. Step 3: Cross multiply
   31,430x = 67,072 × 67,072
4. Step 4: Simplify right side
   31,430x = 4,498,653,184
5. Step 5: Solve for x
   x = 4,498,653,184/31,430
6. Step 6: Final answer
   x = 143,132.46