Home / 1,686-2,640

Finding the Third Proportional to 1,686 and 2,640

Calculator

Solution

The third proportional to 1,686 and 2,640 is: 4,133.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,686 : 2,640 = 2,640 : x
  2. Step 2: Convert to fraction form
    1,686/2,640 = 2,640/x
  3. Step 3: Cross multiply
    1,686x = 2,640 × 2,640
  4. Step 4: Simplify right side
    1,686x = 6,969,600
  5. Step 5: Solve for x
    x = 6,969,600/1,686
  6. Step 6: Final answer
    x = 4,133.81

Related Problems

Find third proportional to 843 and 1,320
Half scale
Find third proportional to 3,372 and 5,280
Double scale
Find third proportional to 1,688 and 2,643
Similar ratio
Find third proportional to 2,529 and 3,960
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.57) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.