Home / 687-999

Finding the Third Proportional to 687 and 999

Calculator

Solution

The third proportional to 687 and 999 is: 1,452.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    687 : 999 = 999 : x
  2. Step 2: Convert to fraction form
    687/999 = 999/x
  3. Step 3: Cross multiply
    687x = 999 × 999
  4. Step 4: Simplify right side
    687x = 998,001
  5. Step 5: Solve for x
    x = 998,001/687
  6. Step 6: Final answer
    x = 1,452.69

Related Problems

Find third proportional to 343.50 and 499.50
Half scale
Find third proportional to 1,374 and 1,998
Double scale
Find third proportional to 689 and 1,002
Similar ratio
Find third proportional to 1,030.50 and 1,498.50
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.45) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.