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Finding the Fourth Proportional to 8.21, 12.33 and 4.21

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Solution

The fourth proportional to 8.21, 12.33 and 4.21 is: 6.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    8.21 : 12.33 = 4.21 : x
  2. Step 2: Convert to fraction form
    8.21/12.33 = 4.21/x
  3. Step 3: Cross multiply
    8.21x = 12.33 × 4.21
  4. Step 4: Simplify right side
    8.21x = 51.83
  5. Step 5: Solve for x
    x = 51.83/8.21
  6. Step 6: Final answer
    x = 6.31

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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.