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Finding the Third Proportional to 5.15 and 10.71

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Solution

The third proportional to 5.15 and 10.71 is: 22.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    5.15 : 10.71 = 10.71 : x
  2. Step 2: Convert to fraction form
    5.15/10.71 = 10.71/x
  3. Step 3: Cross multiply
    5.15x = 10.71 × 10.71
  4. Step 4: Simplify right side
    5.15x = 114.73
  5. Step 5: Solve for x
    x = 114.73/5.15
  6. Step 6: Final answer
    x = 22.27

Related Problems

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Double scale
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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (2.08) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.