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Finding the Fourth Proportional to 640.82, 961.38 and 270.42

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Solution

The fourth proportional to 640.82, 961.38 and 270.42 is: 405.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.82 : 961.38 = 270.42 : x
  2. Step 2: Convert to fraction form
    640.82/961.38 = 270.42/x
  3. Step 3: Cross multiply
    640.82x = 961.38 × 270.42
  4. Step 4: Simplify right side
    640.82x = 259,970.22
  5. Step 5: Solve for x
    x = 259,970.22/640.82
  6. Step 6: Final answer
    x = 405.68

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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.