Home / 406.13-643.31

Finding the Third Proportional to 406.13 and 643.31

Calculator

Solution

The third proportional to 406.13 and 643.31 is: 1,019.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    406.13 : 643.31 = 643.31 : x
  2. Step 2: Convert to fraction form
    406.13/643.31 = 643.31/x
  3. Step 3: Cross multiply
    406.13x = 643.31 × 643.31
  4. Step 4: Simplify right side
    406.13x = 413,850.97
  5. Step 5: Solve for x
    x = 413,850.97/406.13
  6. Step 6: Final answer
    x = 1,019.02

Related Problems

Find third proportional to 203.06 and 321.66
Half scale
Find third proportional to 812.25 and 1,286.63
Double scale
Find third proportional to 408 and 646
Similar ratio
Find third proportional to 609.19 and 964.97
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.58) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.