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Finding the Fourth Proportional to 2.81, 3.87 and 2.20

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Solution

The fourth proportional to 2.81, 3.87 and 2.20 is: 3.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    2.81 : 3.87 = 2.20 : x
  2. Step 2: Convert to fraction form
    2.81/3.87 = 2.20/x
  3. Step 3: Cross multiply
    2.81x = 3.87 × 2.20
  4. Step 4: Simplify right side
    2.81x = 8.49
  5. Step 5: Solve for x
    x = 8.49/2.81
  6. Step 6: Final answer
    x = 3.03

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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.