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Finding the Fourth Proportional to 38.90, 58.11 and 38.72

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Solution

The fourth proportional to 38.90, 58.11 and 38.72 is: 57.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    38.90 : 58.11 = 38.72 : x
  2. Step 2: Convert to fraction form
    38.90/58.11 = 38.72/x
  3. Step 3: Cross multiply
    38.90x = 58.11 × 38.72
  4. Step 4: Simplify right side
    38.90x = 2,250.02
  5. Step 5: Solve for x
    x = 2,250.02/38.90
  6. Step 6: Final answer
    x = 57.84

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.