Home / 415.50-687.75

Finding the Third Proportional to 415.50 and 687.75

Calculator

Solution

The third proportional to 415.50 and 687.75 is: 1,138.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    415.50 : 687.75 = 687.75 : x
  2. Step 2: Convert to fraction form
    415.50/687.75 = 687.75/x
  3. Step 3: Cross multiply
    415.50x = 687.75 × 687.75
  4. Step 4: Simplify right side
    415.50x = 473,000.06
  5. Step 5: Solve for x
    x = 473,000.06/415.50
  6. Step 6: Final answer
    x = 1,138.39

Related Problems

Find third proportional to 207.75 and 343.88
Half scale
Find third proportional to 831 and 1,375.50
Double scale
Find third proportional to 418 and 691
Similar ratio
Find third proportional to 623.25 and 1,031.63
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.66) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.