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Finding the Fourth Proportional to 387.91, 581.31 and 291.79

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Solution

The fourth proportional to 387.91, 581.31 and 291.79 is: 437.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.91 : 581.31 = 291.79 : x
  2. Step 2: Convert to fraction form
    387.91/581.31 = 291.79/x
  3. Step 3: Cross multiply
    387.91x = 581.31 × 291.79
  4. Step 4: Simplify right side
    387.91x = 169,620.44
  5. Step 5: Solve for x
    x = 169,620.44/387.91
  6. Step 6: Final answer
    x = 437.27

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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.