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Finding the Fourth Proportional to 38.78, 53.16 and 38.09

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Solution

The fourth proportional to 38.78, 53.16 and 38.09 is: 52.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    38.78 : 53.16 = 38.09 : x
  2. Step 2: Convert to fraction form
    38.78/53.16 = 38.09/x
  3. Step 3: Cross multiply
    38.78x = 53.16 × 38.09
  4. Step 4: Simplify right side
    38.78x = 2,025.14
  5. Step 5: Solve for x
    x = 2,025.14/38.78
  6. Step 6: Final answer
    x = 52.22

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.