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Finding the Fourth Proportional to 5.43, 8.20 and 5.09

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Solution

The fourth proportional to 5.43, 8.20 and 5.09 is: 7.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    5.43 : 8.20 = 5.09 : x
  2. Step 2: Convert to fraction form
    5.43/8.20 = 5.09/x
  3. Step 3: Cross multiply
    5.43x = 8.20 × 5.09
  4. Step 4: Simplify right side
    5.43x = 41.73
  5. Step 5: Solve for x
    x = 41.73/5.43
  6. Step 6: Final answer
    x = 7.69

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.