Home / 513-687

Finding the Third Proportional to 513 and 687

Calculator

Solution

The third proportional to 513 and 687 is: 920.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    513 : 687 = 687 : x
  2. Step 2: Convert to fraction form
    513/687 = 687/x
  3. Step 3: Cross multiply
    513x = 687 × 687
  4. Step 4: Simplify right side
    513x = 471,969
  5. Step 5: Solve for x
    x = 471,969/513
  6. Step 6: Final answer
    x = 920.02

Related Problems

Find third proportional to 256.50 and 343.50
Half scale
Find third proportional to 1,026 and 1,374
Double scale
Find third proportional to 515 and 690
Similar ratio
Find third proportional to 769.50 and 1,030.50
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.34) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.