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Finding the Fourth Proportional to 3.71, 5.12 and 2.09

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Solution

The fourth proportional to 3.71, 5.12 and 2.09 is: 2.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    3.71 : 5.12 = 2.09 : x
  2. Step 2: Convert to fraction form
    3.71/5.12 = 2.09/x
  3. Step 3: Cross multiply
    3.71x = 5.12 × 2.09
  4. Step 4: Simplify right side
    3.71x = 10.72
  5. Step 5: Solve for x
    x = 10.72/3.71
  6. Step 6: Final answer
    x = 2.89

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.