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Finding the Fourth Proportional to 38.78, 58.18 and 28.08

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Solution

The fourth proportional to 38.78, 58.18 and 28.08 is: 42.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    38.78 : 58.18 = 28.08 : x
  2. Step 2: Convert to fraction form
    38.78/58.18 = 28.08/x
  3. Step 3: Cross multiply
    38.78x = 58.18 × 28.08
  4. Step 4: Simplify right side
    38.78x = 1,633.55
  5. Step 5: Solve for x
    x = 1,633.55/38.78
  6. Step 6: Final answer
    x = 42.12

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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.