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Finding the Fourth Proportional to 3.70, 5.09 and 3.09

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Solution

The fourth proportional to 3.70, 5.09 and 3.09 is: 4.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    3.70 : 5.09 = 3.09 : x
  2. Step 2: Convert to fraction form
    3.70/5.09 = 3.09/x
  3. Step 3: Cross multiply
    3.70x = 5.09 × 3.09
  4. Step 4: Simplify right side
    3.70x = 15.73
  5. Step 5: Solve for x
    x = 15.73/3.70
  6. Step 6: Final answer
    x = 4.25

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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.