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Finding the Fourth Proportional to 428.69, 591.49 and 289.07

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Solution

The fourth proportional to 428.69, 591.49 and 289.07 is: 398.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.69 : 591.49 = 289.07 : x
  2. Step 2: Convert to fraction form
    428.69/591.49 = 289.07/x
  3. Step 3: Cross multiply
    428.69x = 591.49 × 289.07
  4. Step 4: Simplify right side
    428.69x = 170,978.33
  5. Step 5: Solve for x
    x = 170,978.33/428.69
  6. Step 6: Final answer
    x = 398.84

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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.