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Finding the Fourth Proportional to 643.13, 964.82 and 258.38

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Solution

The fourth proportional to 643.13, 964.82 and 258.38 is: 387.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.13 : 964.82 = 258.38 : x
  2. Step 2: Convert to fraction form
    643.13/964.82 = 258.38/x
  3. Step 3: Cross multiply
    643.13x = 964.82 × 258.38
  4. Step 4: Simplify right side
    643.13x = 249,286.01
  5. Step 5: Solve for x
    x = 249,286.01/643.13
  6. Step 6: Final answer
    x = 387.62

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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.