Home / 687.75-870.75

Finding the Third Proportional to 687.75 and 870.75

Calculator

Solution

The third proportional to 687.75 and 870.75 is: 1,102.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    687.75 : 870.75 = 870.75 : x
  2. Step 2: Convert to fraction form
    687.75/870.75 = 870.75/x
  3. Step 3: Cross multiply
    687.75x = 870.75 × 870.75
  4. Step 4: Simplify right side
    687.75x = 758,205.56
  5. Step 5: Solve for x
    x = 758,205.56/687.75
  6. Step 6: Final answer
    x = 1,102.44

Related Problems

Find third proportional to 343.88 and 435.38
Half scale
Find third proportional to 1,375.50 and 1,741.50
Double scale
Find third proportional to 690 and 873
Similar ratio
Find third proportional to 1,031.63 and 1,306.13
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.27) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.