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Finding the Fourth Proportional to 643.87, 965.34 and 330.75

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Solution

The fourth proportional to 643.87, 965.34 and 330.75 is: 495.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.87 : 965.34 = 330.75 : x
  2. Step 2: Convert to fraction form
    643.87/965.34 = 330.75/x
  3. Step 3: Cross multiply
    643.87x = 965.34 × 330.75
  4. Step 4: Simplify right side
    643.87x = 319,281.38
  5. Step 5: Solve for x
    x = 319,281.38/643.87
  6. Step 6: Final answer
    x = 495.88

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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.