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Finding the Fourth Proportional to 14.29, 21.31 and 13.78

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Solution

The fourth proportional to 14.29, 21.31 and 13.78 is: 20.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    14.29 : 21.31 = 13.78 : x
  2. Step 2: Convert to fraction form
    14.29/21.31 = 13.78/x
  3. Step 3: Cross multiply
    14.29x = 21.31 × 13.78
  4. Step 4: Simplify right side
    14.29x = 293.55
  5. Step 5: Solve for x
    x = 293.55/14.29
  6. Step 6: Final answer
    x = 20.55

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.