Finding the Third Proportional to 31,216 and 67,688

Step by Step Solution

1. Step 1: Write the proportion equation
   31,216 : 67,688 = 67,688 : x
2. Step 2: Convert to fraction form
   31,216/67,688 = 67,688/x
3. Step 3: Cross multiply
   31,216x = 67,688 × 67,688
4. Step 4: Simplify right side
   31,216x = 4,581,665,344
5. Step 5: Solve for x
   x = 4,581,665,344/31,216
6. Step 6: Final answer
   x = 146,772.98