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Finding the Fourth Proportional to 428.29, 590.49 and 280.67

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Solution

The fourth proportional to 428.29, 590.49 and 280.67 is: 386.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.29 : 590.49 = 280.67 : x
  2. Step 2: Convert to fraction form
    428.29/590.49 = 280.67/x
  3. Step 3: Cross multiply
    428.29x = 590.49 × 280.67
  4. Step 4: Simplify right side
    428.29x = 165,729.88
  5. Step 5: Solve for x
    x = 165,729.88/428.29
  6. Step 6: Final answer
    x = 386.96

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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.