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Finding the Fourth Proportional to 18.71, 28.07 and 5.19

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Solution

The fourth proportional to 18.71, 28.07 and 5.19 is: 7.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    18.71 : 28.07 = 5.19 : x
  2. Step 2: Convert to fraction form
    18.71/28.07 = 5.19/x
  3. Step 3: Cross multiply
    18.71x = 28.07 × 5.19
  4. Step 4: Simplify right side
    18.71x = 145.57
  5. Step 5: Solve for x
    x = 145.57/18.71
  6. Step 6: Final answer
    x = 7.78

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.