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Finding the Fourth Proportional to 3.79, 5.21 and 3.38

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Solution

The fourth proportional to 3.79, 5.21 and 3.38 is: 4.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    3.79 : 5.21 = 3.38 : x
  2. Step 2: Convert to fraction form
    3.79/5.21 = 3.38/x
  3. Step 3: Cross multiply
    3.79x = 5.21 × 3.38
  4. Step 4: Simplify right side
    3.79x = 17.61
  5. Step 5: Solve for x
    x = 17.61/3.79
  6. Step 6: Final answer
    x = 4.65

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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.