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Finding the Fourth Proportional to 5.71, 7.88 and 3.89

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Solution

The fourth proportional to 5.71, 7.88 and 3.89 is: 5.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    5.71 : 7.88 = 3.89 : x
  2. Step 2: Convert to fraction form
    5.71/7.88 = 3.89/x
  3. Step 3: Cross multiply
    5.71x = 7.88 × 3.89
  4. Step 4: Simplify right side
    5.71x = 30.65
  5. Step 5: Solve for x
    x = 30.65/5.71
  6. Step 6: Final answer
    x = 5.37

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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.