Home / 789-861

Finding the Third Proportional to 789 and 861

Calculator

Solution

The third proportional to 789 and 861 is: 939.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    789 : 861 = 861 : x
  2. Step 2: Convert to fraction form
    789/861 = 861/x
  3. Step 3: Cross multiply
    789x = 861 × 861
  4. Step 4: Simplify right side
    789x = 741,321
  5. Step 5: Solve for x
    x = 741,321/789
  6. Step 6: Final answer
    x = 939.57

Related Problems

Find third proportional to 394.50 and 430.50
Half scale
Find third proportional to 1,578 and 1,722
Double scale
Find third proportional to 791 and 863
Similar ratio
Find third proportional to 1,183.50 and 1,291.50
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.09) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.