Finding the Third Proportional to 88.50 and 139.13

Step by Step Solution

1. Step 1: Write the proportion equation
   88.50 : 139.13 = 139.13 : x
2. Step 2: Convert to fraction form
   88.50/139.13 = 139.13/x
3. Step 3: Cross multiply
   88.50x = 139.13 × 139.13
4. Step 4: Simplify right side
   88.50x = 19,355.77
5. Step 5: Solve for x
   x = 19,355.77/88.50
6. Step 6: Final answer
   x = 218.71