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Finding the Fourth Proportional to 6.89, 10.29 and 6.21

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Solution

The fourth proportional to 6.89, 10.29 and 6.21 is: 9.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    6.89 : 10.29 = 6.21 : x
  2. Step 2: Convert to fraction form
    6.89/10.29 = 6.21/x
  3. Step 3: Cross multiply
    6.89x = 10.29 × 6.21
  4. Step 4: Simplify right side
    6.89x = 63.90
  5. Step 5: Solve for x
    x = 63.90/6.89
  6. Step 6: Final answer
    x = 9.28

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.