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Finding the Fourth Proportional to 28.61, 39.47 and 19.40

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Solution

The fourth proportional to 28.61, 39.47 and 19.40 is: 26.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    28.61 : 39.47 = 19.40 : x
  2. Step 2: Convert to fraction form
    28.61/39.47 = 19.40/x
  3. Step 3: Cross multiply
    28.61x = 39.47 × 19.40
  4. Step 4: Simplify right side
    28.61x = 765.62
  5. Step 5: Solve for x
    x = 765.62/28.61
  6. Step 6: Final answer
    x = 26.76

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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.