Home / 30-65

Finding the Third Proportional to 30 and 65

Calculator

Solution

The third proportional to 30 and 65 is: 140.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    30 : 65 = 65 : x
  2. Step 2: Convert to fraction form
    30/65 = 65/x
  3. Step 3: Cross multiply
    30x = 65 × 65
  4. Step 4: Simplify right side
    30x = 4,225
  5. Step 5: Solve for x
    x = 4,225/30
  6. Step 6: Final answer
    x = 140.83

Related Problems

Find third proportional to 15 and 32.50
Half scale
Find third proportional to 60 and 130
Double scale
Find third proportional to 32 and 69
Similar ratio
Find third proportional to 45 and 97.50
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (2.17) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.