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Finding the Fourth Proportional to 15.29, 21.21 and 13.77

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Solution

The fourth proportional to 15.29, 21.21 and 13.77 is: 19.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    15.29 : 21.21 = 13.77 : x
  2. Step 2: Convert to fraction form
    15.29/21.21 = 13.77/x
  3. Step 3: Cross multiply
    15.29x = 21.21 × 13.77
  4. Step 4: Simplify right side
    15.29x = 292.11
  5. Step 5: Solve for x
    x = 292.11/15.29
  6. Step 6: Final answer
    x = 19.10

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.