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Finding the Fourth Proportional to 15.41, 21.21 and 13.65

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Solution

The fourth proportional to 15.41, 21.21 and 13.65 is: 18.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    15.41 : 21.21 = 13.65 : x
  2. Step 2: Convert to fraction form
    15.41/21.21 = 13.65/x
  3. Step 3: Cross multiply
    15.41x = 21.21 × 13.65
  4. Step 4: Simplify right side
    15.41x = 289.52
  5. Step 5: Solve for x
    x = 289.52/15.41
  6. Step 6: Final answer
    x = 18.79

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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.