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Finding the Fourth Proportional to 19.13, 28.71 and 8.30

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Solution

The fourth proportional to 19.13, 28.71 and 8.30 is: 12.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    19.13 : 28.71 = 8.30 : x
  2. Step 2: Convert to fraction form
    19.13/28.71 = 8.30/x
  3. Step 3: Cross multiply
    19.13x = 28.71 × 8.30
  4. Step 4: Simplify right side
    19.13x = 238.25
  5. Step 5: Solve for x
    x = 238.25/19.13
  6. Step 6: Final answer
    x = 12.45

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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.