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Finding the Fourth Proportional to 643.07, 964.91 and 204.39

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Solution

The fourth proportional to 643.07, 964.91 and 204.39 is: 306.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.07 : 964.91 = 204.39 : x
  2. Step 2: Convert to fraction form
    643.07/964.91 = 204.39/x
  3. Step 3: Cross multiply
    643.07x = 964.91 × 204.39
  4. Step 4: Simplify right side
    643.07x = 197,218.47
  5. Step 5: Solve for x
    x = 197,218.47/643.07
  6. Step 6: Final answer
    x = 306.68

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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.