Home / 12.99-20.20

Finding the Third Proportional to 12.99 and 20.20

Calculator

Solution

The third proportional to 12.99 and 20.20 is: 31.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    12.99 : 20.20 = 20.20 : x
  2. Step 2: Convert to fraction form
    12.99/20.20 = 20.20/x
  3. Step 3: Cross multiply
    12.99x = 20.20 × 20.20
  4. Step 4: Simplify right side
    12.99x = 408.06
  5. Step 5: Solve for x
    x = 408.06/12.99
  6. Step 6: Final answer
    x = 31.41

Related Problems

Find third proportional to 6.50 and 10.10
Half scale
Find third proportional to 25.98 and 40.40
Double scale
Find third proportional to 15 and 23
Similar ratio
Find third proportional to 19.49 and 30.30
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.55) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.