Home / 811-1,728

Finding the Third Proportional to 811 and 1,728

Calculator

Solution

The third proportional to 811 and 1,728 is: 3,681.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    811 : 1,728 = 1,728 : x
  2. Step 2: Convert to fraction form
    811/1,728 = 1,728/x
  3. Step 3: Cross multiply
    811x = 1,728 × 1,728
  4. Step 4: Simplify right side
    811x = 2,985,984
  5. Step 5: Solve for x
    x = 2,985,984/811
  6. Step 6: Final answer
    x = 3,681.85

Related Problems

Find third proportional to 405.50 and 864
Half scale
Find third proportional to 1,622 and 3,456
Double scale
Find third proportional to 813 and 1,732
Similar ratio
Find third proportional to 1,216.50 and 2,592
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (2.13) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.