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Finding the Fourth Proportional to 28.78, 39.67 and 25.73

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Solution

The fourth proportional to 28.78, 39.67 and 25.73 is: 35.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    28.78 : 39.67 = 25.73 : x
  2. Step 2: Convert to fraction form
    28.78/39.67 = 25.73/x
  3. Step 3: Cross multiply
    28.78x = 39.67 × 25.73
  4. Step 4: Simplify right side
    28.78x = 1,020.71
  5. Step 5: Solve for x
    x = 1,020.71/28.78
  6. Step 6: Final answer
    x = 35.47

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.