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Finding the Fourth Proportional to 428.31, 590.97 and 288.72

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Solution

The fourth proportional to 428.31, 590.97 and 288.72 is: 398.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.31 : 590.97 = 288.72 : x
  2. Step 2: Convert to fraction form
    428.31/590.97 = 288.72/x
  3. Step 3: Cross multiply
    428.31x = 590.97 × 288.72
  4. Step 4: Simplify right side
    428.31x = 170,624.86
  5. Step 5: Solve for x
    x = 170,624.86/428.31
  6. Step 6: Final answer
    x = 398.37

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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.