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Finding the Fourth Proportional to 19.39, 26.79 and 15.79

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Solution

The fourth proportional to 19.39, 26.79 and 15.79 is: 21.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    19.39 : 26.79 = 15.79 : x
  2. Step 2: Convert to fraction form
    19.39/26.79 = 15.79/x
  3. Step 3: Cross multiply
    19.39x = 26.79 × 15.79
  4. Step 4: Simplify right side
    19.39x = 423.01
  5. Step 5: Solve for x
    x = 423.01/19.39
  6. Step 6: Final answer
    x = 21.82

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.