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Finding the Fourth Proportional to 28.67, 39.02 and 28.40

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Solution

The fourth proportional to 28.67, 39.02 and 28.40 is: 38.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    28.67 : 39.02 = 28.40 : x
  2. Step 2: Convert to fraction form
    28.67/39.02 = 28.40/x
  3. Step 3: Cross multiply
    28.67x = 39.02 × 28.40
  4. Step 4: Simplify right side
    28.67x = 1,108.17
  5. Step 5: Solve for x
    x = 1,108.17/28.67
  6. Step 6: Final answer
    x = 38.65

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Why These Related Problems?

These problems maintain the same ratio (1.36) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.