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Finding the Fourth Proportional to 12.10, 18.17 and 8.90

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Solution

The fourth proportional to 12.10, 18.17 and 8.90 is: 13.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    12.10 : 18.17 = 8.90 : x
  2. Step 2: Convert to fraction form
    12.10/18.17 = 8.90/x
  3. Step 3: Cross multiply
    12.10x = 18.17 × 8.90
  4. Step 4: Simplify right side
    12.10x = 161.71
  5. Step 5: Solve for x
    x = 161.71/12.10
  6. Step 6: Final answer
    x = 13.36

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.