Finding the Third Proportional to 111.28 and 242.78

Step by Step Solution

1. Step 1: Write the proportion equation
   111.28 : 242.78 = 242.78 : x
2. Step 2: Convert to fraction form
   111.28/242.78 = 242.78/x
3. Step 3: Cross multiply
   111.28x = 242.78 × 242.78
4. Step 4: Simplify right side
   111.28x = 58,942.74
5. Step 5: Solve for x
   x = 58,942.74/111.28
6. Step 6: Final answer
   x = 529.67