Home / 665-729

Finding the Third Proportional to 665 and 729

Calculator

Solution

The third proportional to 665 and 729 is: 799.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    665 : 729 = 729 : x
  2. Step 2: Convert to fraction form
    665/729 = 729/x
  3. Step 3: Cross multiply
    665x = 729 × 729
  4. Step 4: Simplify right side
    665x = 531,441
  5. Step 5: Solve for x
    x = 531,441/665
  6. Step 6: Final answer
    x = 799.16

Related Problems

Find third proportional to 332.50 and 364.50
Half scale
Find third proportional to 1,330 and 1,458
Double scale
Find third proportional to 667 and 731
Similar ratio
Find third proportional to 997.50 and 1,093.50
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.10) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.