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Finding the Fourth Proportional to 13.33, 20 and 5.21

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Solution

The fourth proportional to 13.33, 20 and 5.21 is: 7.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    13.33 : 20 = 5.21 : x
  2. Step 2: Convert to fraction form
    13.33/20 = 5.21/x
  3. Step 3: Cross multiply
    13.33x = 20 × 5.21
  4. Step 4: Simplify right side
    13.33x = 104.20
  5. Step 5: Solve for x
    x = 104.20/13.33
  6. Step 6: Final answer
    x = 7.82

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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.