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Finding the Fourth Proportional to 3.72, 5.13 and 3.21

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Solution

The fourth proportional to 3.72, 5.13 and 3.21 is: 4.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    3.72 : 5.13 = 3.21 : x
  2. Step 2: Convert to fraction form
    3.72/5.13 = 3.21/x
  3. Step 3: Cross multiply
    3.72x = 5.13 × 3.21
  4. Step 4: Simplify right side
    3.72x = 16.47
  5. Step 5: Solve for x
    x = 16.47/3.72
  6. Step 6: Final answer
    x = 4.43

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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.