Home / 470-643

Finding the Third Proportional to 470 and 643

Calculator

Solution

The third proportional to 470 and 643 is: 879.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    470 : 643 = 643 : x
  2. Step 2: Convert to fraction form
    470/643 = 643/x
  3. Step 3: Cross multiply
    470x = 643 × 643
  4. Step 4: Simplify right side
    470x = 413,449
  5. Step 5: Solve for x
    x = 413,449/470
  6. Step 6: Final answer
    x = 879.68

Related Problems

Find third proportional to 235 and 321.50
Half scale
Find third proportional to 940 and 1,286
Double scale
Find third proportional to 472 and 646
Similar ratio
Find third proportional to 705 and 964.50
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.