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Finding the Fourth Proportional to 3.42, 5.12 and 1.91

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Solution

The fourth proportional to 3.42, 5.12 and 1.91 is: 2.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    3.42 : 5.12 = 1.91 : x
  2. Step 2: Convert to fraction form
    3.42/5.12 = 1.91/x
  3. Step 3: Cross multiply
    3.42x = 5.12 × 1.91
  4. Step 4: Simplify right side
    3.42x = 9.78
  5. Step 5: Solve for x
    x = 9.78/3.42
  6. Step 6: Final answer
    x = 2.86

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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.