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Finding the Fourth Proportional to 25.20, 34.78 and 14.28

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Solution

The fourth proportional to 25.20, 34.78 and 14.28 is: 19.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    25.20 : 34.78 = 14.28 : x
  2. Step 2: Convert to fraction form
    25.20/34.78 = 14.28/x
  3. Step 3: Cross multiply
    25.20x = 34.78 × 14.28
  4. Step 4: Simplify right side
    25.20x = 496.66
  5. Step 5: Solve for x
    x = 496.66/25.20
  6. Step 6: Final answer
    x = 19.71

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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.