Finding the Third Proportional to 137.88 and 288.69

Step by Step Solution

1. Step 1: Write the proportion equation
   137.88 : 288.69 = 288.69 : x
2. Step 2: Convert to fraction form
   137.88/288.69 = 288.69/x
3. Step 3: Cross multiply
   137.88x = 288.69 × 288.69
4. Step 4: Simplify right side
   137.88x = 83,340.47
5. Step 5: Solve for x
   x = 83,340.47/137.88
6. Step 6: Final answer
   x = 604.46