Home / 780.50-1,687

Finding the Third Proportional to 780.50 and 1,687

Calculator

Solution

The third proportional to 780.50 and 1,687 is: 3,646.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.50 : 1,687 = 1,687 : x
  2. Step 2: Convert to fraction form
    780.50/1,687 = 1,687/x
  3. Step 3: Cross multiply
    780.50x = 1,687 × 1,687
  4. Step 4: Simplify right side
    780.50x = 2,845,969
  5. Step 5: Solve for x
    x = 2,845,969/780.50
  6. Step 6: Final answer
    x = 3,646.34

Related Problems

Find third proportional to 390.25 and 843.50
Half scale
Find third proportional to 1,561 and 3,374
Double scale
Find third proportional to 783 and 1,691
Similar ratio
Find third proportional to 1,170.75 and 2,530.50
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (2.16) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.