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Finding the Third Proportional to 21.40 and 28.55

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Solution

The third proportional to 21.40 and 28.55 is: 38.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    21.40 : 28.55 = 28.55 : x
  2. Step 2: Convert to fraction form
    21.40/28.55 = 28.55/x
  3. Step 3: Cross multiply
    21.40x = 28.55 × 28.55
  4. Step 4: Simplify right side
    21.40x = 814.92
  5. Step 5: Solve for x
    x = 814.92/21.40
  6. Step 6: Final answer
    x = 38.08

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Why These Related Problems?

These problems maintain the same ratio (1.33) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.