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Finding the Fourth Proportional to 21.49, 29.80 and 19.97

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Solution

The fourth proportional to 21.49, 29.80 and 19.97 is: 27.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    21.49 : 29.80 = 19.97 : x
  2. Step 2: Convert to fraction form
    21.49/29.80 = 19.97/x
  3. Step 3: Cross multiply
    21.49x = 29.80 × 19.97
  4. Step 4: Simplify right side
    21.49x = 595.11
  5. Step 5: Solve for x
    x = 595.11/21.49
  6. Step 6: Final answer
    x = 27.69

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.