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Finding the Fourth Proportional to 387.20, 579.89 and 299.72

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Solution

The fourth proportional to 387.20, 579.89 and 299.72 is: 448.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.20 : 579.89 = 299.72 : x
  2. Step 2: Convert to fraction form
    387.20/579.89 = 299.72/x
  3. Step 3: Cross multiply
    387.20x = 579.89 × 299.72
  4. Step 4: Simplify right side
    387.20x = 173,804.63
  5. Step 5: Solve for x
    x = 173,804.63/387.20
  6. Step 6: Final answer
    x = 448.88

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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.