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Finding the Fourth Proportional to 3.85, 5.28 and 3.78

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Solution

The fourth proportional to 3.85, 5.28 and 3.78 is: 5.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    3.85 : 5.28 = 3.78 : x
  2. Step 2: Convert to fraction form
    3.85/5.28 = 3.78/x
  3. Step 3: Cross multiply
    3.85x = 5.28 × 3.78
  4. Step 4: Simplify right side
    3.85x = 19.97
  5. Step 5: Solve for x
    x = 19.97/3.85
  6. Step 6: Final answer
    x = 5.19

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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.