Finding the Third Proportional to 89.75 and 139.19

Step by Step Solution

1. Step 1: Write the proportion equation
   89.75 : 139.19 = 139.19 : x
2. Step 2: Convert to fraction form
   89.75/139.19 = 139.19/x
3. Step 3: Cross multiply
   89.75x = 139.19 × 139.19
4. Step 4: Simplify right side
   89.75x = 19,373.16
5. Step 5: Solve for x
   x = 19,373.16/89.75
6. Step 6: Final answer
   x = 215.86