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Finding the Fourth Proportional to 4.91, 6.78 and 2.87

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Solution

The fourth proportional to 4.91, 6.78 and 2.87 is: 3.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    4.91 : 6.78 = 2.87 : x
  2. Step 2: Convert to fraction form
    4.91/6.78 = 2.87/x
  3. Step 3: Cross multiply
    4.91x = 6.78 × 2.87
  4. Step 4: Simplify right side
    4.91x = 19.41
  5. Step 5: Solve for x
    x = 19.41/4.91
  6. Step 6: Final answer
    x = 3.95

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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.