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Finding the Fourth Proportional to 28.82, 39.80 and 19.61

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Solution

The fourth proportional to 28.82, 39.80 and 19.61 is: 27.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    28.82 : 39.80 = 19.61 : x
  2. Step 2: Convert to fraction form
    28.82/39.80 = 19.61/x
  3. Step 3: Cross multiply
    28.82x = 39.80 × 19.61
  4. Step 4: Simplify right side
    28.82x = 780.38
  5. Step 5: Solve for x
    x = 780.38/28.82
  6. Step 6: Final answer
    x = 27.08

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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.