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Finding the Fourth Proportional to 21.11, 29.13 and 15.29

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Solution

The fourth proportional to 21.11, 29.13 and 15.29 is: 21.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    21.11 : 29.13 = 15.29 : x
  2. Step 2: Convert to fraction form
    21.11/29.13 = 15.29/x
  3. Step 3: Cross multiply
    21.11x = 29.13 × 15.29
  4. Step 4: Simplify right side
    21.11x = 445.30
  5. Step 5: Solve for x
    x = 445.30/21.11
  6. Step 6: Final answer
    x = 21.10

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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.