Home / 521-628

Finding the Third Proportional to 521 and 628

Calculator

Solution

The third proportional to 521 and 628 is: 756.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    521 : 628 = 628 : x
  2. Step 2: Convert to fraction form
    521/628 = 628/x
  3. Step 3: Cross multiply
    521x = 628 × 628
  4. Step 4: Simplify right side
    521x = 394,384
  5. Step 5: Solve for x
    x = 394,384/521
  6. Step 6: Final answer
    x = 756.98

Related Problems

Find third proportional to 260.50 and 314
Half scale
Find third proportional to 1,042 and 1,256
Double scale
Find third proportional to 523 and 630
Similar ratio
Find third proportional to 781.50 and 942
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.21) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.