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Finding the Fourth Proportional to 5.49, 8.21 and 5.31

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Solution

The fourth proportional to 5.49, 8.21 and 5.31 is: 7.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    5.49 : 8.21 = 5.31 : x
  2. Step 2: Convert to fraction form
    5.49/8.21 = 5.31/x
  3. Step 3: Cross multiply
    5.49x = 8.21 × 5.31
  4. Step 4: Simplify right side
    5.49x = 43.60
  5. Step 5: Solve for x
    x = 43.60/5.49
  6. Step 6: Final answer
    x = 7.94

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.