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Finding the Third Proportional to 15.78 and 17.66

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Solution

The third proportional to 15.78 and 17.66 is: 19.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    15.78 : 17.66 = 17.66 : x
  2. Step 2: Convert to fraction form
    15.78/17.66 = 17.66/x
  3. Step 3: Cross multiply
    15.78x = 17.66 × 17.66
  4. Step 4: Simplify right side
    15.78x = 311.76
  5. Step 5: Solve for x
    x = 311.76/15.78
  6. Step 6: Final answer
    x = 19.75

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Why These Related Problems?

These problems maintain the same ratio (1.12) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.