Finding the Third Proportional to 111.50 and 205.50

Step by Step Solution

1. Step 1: Write the proportion equation
   111.50 : 205.50 = 205.50 : x
2. Step 2: Convert to fraction form
   111.50/205.50 = 205.50/x
3. Step 3: Cross multiply
   111.50x = 205.50 × 205.50
4. Step 4: Simplify right side
   111.50x = 42,230.25
5. Step 5: Solve for x
   x = 42,230.25/111.50
6. Step 6: Final answer
   x = 378.75