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Finding the Fourth Proportional to 19.39, 29.05 and 12.15

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Solution

The fourth proportional to 19.39, 29.05 and 12.15 is: 18.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    19.39 : 29.05 = 12.15 : x
  2. Step 2: Convert to fraction form
    19.39/29.05 = 12.15/x
  3. Step 3: Cross multiply
    19.39x = 29.05 × 12.15
  4. Step 4: Simplify right side
    19.39x = 352.75
  5. Step 5: Solve for x
    x = 352.75/19.39
  6. Step 6: Final answer
    x = 18.19

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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.