Finding the Third Proportional to 90.19 and 136.31

Step by Step Solution

1. Step 1: Write the proportion equation
   90.19 : 136.31 = 136.31 : x
2. Step 2: Convert to fraction form
   90.19/136.31 = 136.31/x
3. Step 3: Cross multiply
   90.19x = 136.31 × 136.31
4. Step 4: Simplify right side
   90.19x = 18,581.10
5. Step 5: Solve for x
   x = 18,581.10/90.19
6. Step 6: Final answer
   x = 206.03