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Finding the Fourth Proportional to 13.70, 18.91 and 9.09

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Solution

The fourth proportional to 13.70, 18.91 and 9.09 is: 12.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    13.70 : 18.91 = 9.09 : x
  2. Step 2: Convert to fraction form
    13.70/18.91 = 9.09/x
  3. Step 3: Cross multiply
    13.70x = 18.91 × 9.09
  4. Step 4: Simplify right side
    13.70x = 171.89
  5. Step 5: Solve for x
    x = 171.89/13.70
  6. Step 6: Final answer
    x = 12.55

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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.