Home / 15,728-21,000

Finding the Third Proportional to 15,728 and 21,000

Calculator

Solution

The third proportional to 15,728 and 21,000 is: 28,039.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    15,728 : 21,000 = 21,000 : x
  2. Step 2: Convert to fraction form
    15,728/21,000 = 21,000/x
  3. Step 3: Cross multiply
    15,728x = 21,000 × 21,000
  4. Step 4: Simplify right side
    15,728x = 441,000,000
  5. Step 5: Solve for x
    x = 441,000,000/15,728
  6. Step 6: Final answer
    x = 28,039.17

Related Problems

Find third proportional to 7,864 and 10,500
Half scale
Find third proportional to 31,456 and 42,000
Double scale
Find third proportional to 15,730 and 21,003
Similar ratio
Find third proportional to 23,592 and 31,500
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.34) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.