Finding the Third Proportional to 136.27 and 290.72

Step by Step Solution

1. Step 1: Write the proportion equation
   136.27 : 290.72 = 290.72 : x
2. Step 2: Convert to fraction form
   136.27/290.72 = 290.72/x
3. Step 3: Cross multiply
   136.27x = 290.72 × 290.72
4. Step 4: Simplify right side
   136.27x = 84,520.80
5. Step 5: Solve for x
   x = 84,520.80/136.27
6. Step 6: Final answer
   x = 620.27