Finding the Third Proportional to 90.13 and 139.84

Step by Step Solution

1. Step 1: Write the proportion equation
   90.13 : 139.84 = 139.84 : x
2. Step 2: Convert to fraction form
   90.13/139.84 = 139.84/x
3. Step 3: Cross multiply
   90.13x = 139.84 × 139.84
4. Step 4: Simplify right side
   90.13x = 19,556.27
5. Step 5: Solve for x
   x = 19,556.27/90.13
6. Step 6: Final answer
   x = 216.99