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Finding the Fourth Proportional to 21.05, 29.16 and 19.76

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Solution

The fourth proportional to 21.05, 29.16 and 19.76 is: 27.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    21.05 : 29.16 = 19.76 : x
  2. Step 2: Convert to fraction form
    21.05/29.16 = 19.76/x
  3. Step 3: Cross multiply
    21.05x = 29.16 × 19.76
  4. Step 4: Simplify right side
    21.05x = 576.32
  5. Step 5: Solve for x
    x = 576.32/21.05
  6. Step 6: Final answer
    x = 27.38

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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.