Finding the Third Proportional to 21.85 and 40.55

Step by Step Solution

1. Step 1: Write the proportion equation
   21.85 : 40.55 = 40.55 : x
2. Step 2: Convert to fraction form
   21.85/40.55 = 40.55/x
3. Step 3: Cross multiply
   21.85x = 40.55 × 40.55
4. Step 4: Simplify right side
   21.85x = 1,643.96
5. Step 5: Solve for x
   x = 1,643.96/21.85
6. Step 6: Final answer
   x = 75.24