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Finding the Fourth Proportional to 39.40, 59.09 and 19.09

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Solution

The fourth proportional to 39.40, 59.09 and 19.09 is: 28.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    39.40 : 59.09 = 19.09 : x
  2. Step 2: Convert to fraction form
    39.40/59.09 = 19.09/x
  3. Step 3: Cross multiply
    39.40x = 59.09 × 19.09
  4. Step 4: Simplify right side
    39.40x = 1,127.64
  5. Step 5: Solve for x
    x = 1,127.64/39.40
  6. Step 6: Final answer
    x = 28.62

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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.