Home / 15.86-21.08

Finding the Third Proportional to 15.86 and 21.08

Calculator

Solution

The third proportional to 15.86 and 21.08 is: 28.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    15.86 : 21.08 = 21.08 : x
  2. Step 2: Convert to fraction form
    15.86/21.08 = 21.08/x
  3. Step 3: Cross multiply
    15.86x = 21.08 × 21.08
  4. Step 4: Simplify right side
    15.86x = 444.29
  5. Step 5: Solve for x
    x = 444.29/15.86
  6. Step 6: Final answer
    x = 28.01

Related Problems

Find third proportional to 7.93 and 10.54
Half scale
Find third proportional to 31.72 and 42.16
Double scale
Find third proportional to 18 and 24
Similar ratio
Find third proportional to 23.79 and 31.62
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.33) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.