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Finding the Third Proportional to 1,218 and 1,821

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Solution

The third proportional to 1,218 and 1,821 is: 2,722.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,218 : 1,821 = 1,821 : x
  2. Step 2: Convert to fraction form
    1,218/1,821 = 1,821/x
  3. Step 3: Cross multiply
    1,218x = 1,821 × 1,821
  4. Step 4: Simplify right side
    1,218x = 3,316,041
  5. Step 5: Solve for x
    x = 3,316,041/1,218
  6. Step 6: Final answer
    x = 2,722.53

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.