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Finding the Fourth Proportional to 25.30, 34.87 and 20.71

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Solution

The fourth proportional to 25.30, 34.87 and 20.71 is: 28.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    25.30 : 34.87 = 20.71 : x
  2. Step 2: Convert to fraction form
    25.30/34.87 = 20.71/x
  3. Step 3: Cross multiply
    25.30x = 34.87 × 20.71
  4. Step 4: Simplify right side
    25.30x = 722.16
  5. Step 5: Solve for x
    x = 722.16/25.30
  6. Step 6: Final answer
    x = 28.54

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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.