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Finding the Fourth Proportional to 3.70, 5.11 and 2.09

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Solution

The fourth proportional to 3.70, 5.11 and 2.09 is: 2.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    3.70 : 5.11 = 2.09 : x
  2. Step 2: Convert to fraction form
    3.70/5.11 = 2.09/x
  3. Step 3: Cross multiply
    3.70x = 5.11 × 2.09
  4. Step 4: Simplify right side
    3.70x = 10.67
  5. Step 5: Solve for x
    x = 10.67/3.70
  6. Step 6: Final answer
    x = 2.88

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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.