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Finding the Third Proportional to 4.78 and 10.20

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Solution

The third proportional to 4.78 and 10.20 is: 21.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    4.78 : 10.20 = 10.20 : x
  2. Step 2: Convert to fraction form
    4.78/10.20 = 10.20/x
  3. Step 3: Cross multiply
    4.78x = 10.20 × 10.20
  4. Step 4: Simplify right side
    4.78x = 103.94
  5. Step 5: Solve for x
    x = 103.94/4.78
  6. Step 6: Final answer
    x = 21.74

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Why These Related Problems?

These problems maintain the same ratio (2.13) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.