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Finding the Fourth Proportional to 8.81, 12.15 and 5.17

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Solution

The fourth proportional to 8.81, 12.15 and 5.17 is: 7.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    8.81 : 12.15 = 5.17 : x
  2. Step 2: Convert to fraction form
    8.81/12.15 = 5.17/x
  3. Step 3: Cross multiply
    8.81x = 12.15 × 5.17
  4. Step 4: Simplify right side
    8.81x = 62.79
  5. Step 5: Solve for x
    x = 62.79/8.81
  6. Step 6: Final answer
    x = 7.13

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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.