Finding the Third Proportional to 5.50 and 10.50

Step by Step Solution

1. Step 1: Write the proportion equation
   5.50 : 10.50 = 10.50 : x
2. Step 2: Convert to fraction form
   5.50/10.50 = 10.50/x
3. Step 3: Cross multiply
   5.50x = 10.50 × 10.50
4. Step 4: Simplify right side
   5.50x = 110.25
5. Step 5: Solve for x
   x = 110.25/5.50
6. Step 6: Final answer
   x = 20.05