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Finding the Third Proportional to 17,280 and 18,720

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Solution

The third proportional to 17,280 and 18,720 is: 20,280

Step by Step Solution

  1. Step 1: Write the proportion equation
    17,280 : 18,720 = 18,720 : x
  2. Step 2: Convert to fraction form
    17,280/18,720 = 18,720/x
  3. Step 3: Cross multiply
    17,280x = 18,720 × 18,720
  4. Step 4: Simplify right side
    17,280x = 350,438,400
  5. Step 5: Solve for x
    x = 350,438,400/17,280
  6. Step 6: Final answer
    x = 20,280

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.08) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.