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Finding the Fourth Proportional to 20.82, 28.76 and 15.00

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Solution

The fourth proportional to 20.82, 28.76 and 15.00 is: 20.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    20.82 : 28.76 = 15.00 : x
  2. Step 2: Convert to fraction form
    20.82/28.76 = 15.00/x
  3. Step 3: Cross multiply
    20.82x = 28.76 × 15.00
  4. Step 4: Simplify right side
    20.82x = 431.38
  5. Step 5: Solve for x
    x = 431.38/20.82
  6. Step 6: Final answer
    x = 20.72

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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.