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Finding the Third Proportional to 1,821 and 4,020

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Solution

The third proportional to 1,821 and 4,020 is: 8,874.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,821 : 4,020 = 4,020 : x
  2. Step 2: Convert to fraction form
    1,821/4,020 = 4,020/x
  3. Step 3: Cross multiply
    1,821x = 4,020 × 4,020
  4. Step 4: Simplify right side
    1,821x = 16,160,400
  5. Step 5: Solve for x
    x = 16,160,400/1,821
  6. Step 6: Final answer
    x = 8,874.46

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Why These Related Problems?

These problems maintain the same ratio (2.21) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.