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Finding the Fourth Proportional to 5.91, 8.90 and 5.09

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Solution

The fourth proportional to 5.91, 8.90 and 5.09 is: 7.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    5.91 : 8.90 = 5.09 : x
  2. Step 2: Convert to fraction form
    5.91/8.90 = 5.09/x
  3. Step 3: Cross multiply
    5.91x = 8.90 × 5.09
  4. Step 4: Simplify right side
    5.91x = 45.23
  5. Step 5: Solve for x
    x = 45.23/5.91
  6. Step 6: Final answer
    x = 7.65

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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.