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Finding the Fourth Proportional to 2.87, 3.96 and 2.11

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Solution

The fourth proportional to 2.87, 3.96 and 2.11 is: 2.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    2.87 : 3.96 = 2.11 : x
  2. Step 2: Convert to fraction form
    2.87/3.96 = 2.11/x
  3. Step 3: Cross multiply
    2.87x = 3.96 × 2.11
  4. Step 4: Simplify right side
    2.87x = 8.34
  5. Step 5: Solve for x
    x = 8.34/2.87
  6. Step 6: Final answer
    x = 2.90

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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.