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Finding the Third Proportional to 5.21 and 7.75

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Solution

The third proportional to 5.21 and 7.75 is: 11.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    5.21 : 7.75 = 7.75 : x
  2. Step 2: Convert to fraction form
    5.21/7.75 = 7.75/x
  3. Step 3: Cross multiply
    5.21x = 7.75 × 7.75
  4. Step 4: Simplify right side
    5.21x = 60.11
  5. Step 5: Solve for x
    x = 60.11/5.21
  6. Step 6: Final answer
    x = 11.54

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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.