Home / 316-686

Finding the Third Proportional to 316 and 686

Calculator

Solution

The third proportional to 316 and 686 is: 1,489.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    316 : 686 = 686 : x
  2. Step 2: Convert to fraction form
    316/686 = 686/x
  3. Step 3: Cross multiply
    316x = 686 × 686
  4. Step 4: Simplify right side
    316x = 470,596
  5. Step 5: Solve for x
    x = 470,596/316
  6. Step 6: Final answer
    x = 1,489.23

Related Problems

Find third proportional to 158 and 343
Half scale
Find third proportional to 632 and 1,372
Double scale
Find third proportional to 318 and 690
Similar ratio
Find third proportional to 474 and 1,029
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (2.17) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.