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Finding the Fourth Proportional to 38.15, 57.15 and 20.10

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Solution

The fourth proportional to 38.15, 57.15 and 20.10 is: 30.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    38.15 : 57.15 = 20.10 : x
  2. Step 2: Convert to fraction form
    38.15/57.15 = 20.10/x
  3. Step 3: Cross multiply
    38.15x = 57.15 × 20.10
  4. Step 4: Simplify right side
    38.15x = 1,148.72
  5. Step 5: Solve for x
    x = 1,148.72/38.15
  6. Step 6: Final answer
    x = 30.11

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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.