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Finding the Fourth Proportional to 387, 579.69 and 289.59

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Solution

The fourth proportional to 387, 579.69 and 289.59 is: 433.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    387 : 579.69 = 289.59 : x
  2. Step 2: Convert to fraction form
    387/579.69 = 289.59/x
  3. Step 3: Cross multiply
    387x = 579.69 × 289.59
  4. Step 4: Simplify right side
    387x = 167,872.43
  5. Step 5: Solve for x
    x = 167,872.43/387
  6. Step 6: Final answer
    x = 433.78

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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.