Home / 857-921

Finding the Third Proportional to 857 and 921

Calculator

Solution

The third proportional to 857 and 921 is: 989.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    857 : 921 = 921 : x
  2. Step 2: Convert to fraction form
    857/921 = 921/x
  3. Step 3: Cross multiply
    857x = 921 × 921
  4. Step 4: Simplify right side
    857x = 848,241
  5. Step 5: Solve for x
    x = 848,241/857
  6. Step 6: Final answer
    x = 989.78

Related Problems

Find third proportional to 428.50 and 460.50
Half scale
Find third proportional to 1,714 and 1,842
Double scale
Find third proportional to 859 and 923
Similar ratio
Find third proportional to 1,285.50 and 1,381.50
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.07) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.