Finding the Third Proportional to 67,688 and 139,672

Step by Step Solution

1. Step 1: Write the proportion equation
   67,688 : 139,672 = 139,672 : x
2. Step 2: Convert to fraction form
   67,688/139,672 = 139,672/x
3. Step 3: Cross multiply
   67,688x = 139,672 × 139,672
4. Step 4: Simplify right side
   67,688x = 19,508,267,584
5. Step 5: Solve for x
   x = 19,508,267,584/67,688
6. Step 6: Final answer
   x = 288,208.66