Home / 425-521

Finding the Third Proportional to 425 and 521

Calculator

Solution

The third proportional to 425 and 521 is: 638.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    425 : 521 = 521 : x
  2. Step 2: Convert to fraction form
    425/521 = 521/x
  3. Step 3: Cross multiply
    425x = 521 × 521
  4. Step 4: Simplify right side
    425x = 271,441
  5. Step 5: Solve for x
    x = 271,441/425
  6. Step 6: Final answer
    x = 638.68

Related Problems

Find third proportional to 212.50 and 260.50
Half scale
Find third proportional to 850 and 1,042
Double scale
Find third proportional to 427 and 523
Similar ratio
Find third proportional to 637.50 and 781.50
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.23) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.