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Finding the Fourth Proportional to 4.85, 7.28 and 2.85

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Solution

The fourth proportional to 4.85, 7.28 and 2.85 is: 4.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    4.85 : 7.28 = 2.85 : x
  2. Step 2: Convert to fraction form
    4.85/7.28 = 2.85/x
  3. Step 3: Cross multiply
    4.85x = 7.28 × 2.85
  4. Step 4: Simplify right side
    4.85x = 20.75
  5. Step 5: Solve for x
    x = 20.75/4.85
  6. Step 6: Final answer
    x = 4.28

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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.