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Finding the Fourth Proportional to 11.21, 15.45 and 10

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Solution

The fourth proportional to 11.21, 15.45 and 10 is: 13.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    11.21 : 15.45 = 10 : x
  2. Step 2: Convert to fraction form
    11.21/15.45 = 10/x
  3. Step 3: Cross multiply
    11.21x = 15.45 × 10
  4. Step 4: Simplify right side
    11.21x = 154.50
  5. Step 5: Solve for x
    x = 154.50/11.21
  6. Step 6: Final answer
    x = 13.78

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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.