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Finding the Fourth Proportional to 6.39, 8.82 and 4.21

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Solution

The fourth proportional to 6.39, 8.82 and 4.21 is: 5.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    6.39 : 8.82 = 4.21 : x
  2. Step 2: Convert to fraction form
    6.39/8.82 = 4.21/x
  3. Step 3: Cross multiply
    6.39x = 8.82 × 4.21
  4. Step 4: Simplify right side
    6.39x = 37.13
  5. Step 5: Solve for x
    x = 37.13/6.39
  6. Step 6: Final answer
    x = 5.81

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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.