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Finding the Fourth Proportional to 38.18, 57.20 and 28.10

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Solution

The fourth proportional to 38.18, 57.20 and 28.10 is: 42.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    38.18 : 57.20 = 28.10 : x
  2. Step 2: Convert to fraction form
    38.18/57.20 = 28.10/x
  3. Step 3: Cross multiply
    38.18x = 57.20 × 28.10
  4. Step 4: Simplify right side
    38.18x = 1,607.10
  5. Step 5: Solve for x
    x = 1,607.10/38.18
  6. Step 6: Final answer
    x = 42.10

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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.