Finding the Third Proportional to 21.50 and 28.50

Step by Step Solution

1. Step 1: Write the proportion equation
   21.50 : 28.50 = 28.50 : x
2. Step 2: Convert to fraction form
   21.50/28.50 = 28.50/x
3. Step 3: Cross multiply
   21.50x = 28.50 × 28.50
4. Step 4: Simplify right side
   21.50x = 812.25
5. Step 5: Solve for x
   x = 812.25/21.50
6. Step 6: Final answer
   x = 37.78