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Finding the Fourth Proportional to 643.14, 963.87 and 257.94

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Solution

The fourth proportional to 643.14, 963.87 and 257.94 is: 386.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.14 : 963.87 = 257.94 : x
  2. Step 2: Convert to fraction form
    643.14/963.87 = 257.94/x
  3. Step 3: Cross multiply
    643.14x = 963.87 × 257.94
  4. Step 4: Simplify right side
    643.14x = 248,620.63
  5. Step 5: Solve for x
    x = 248,620.63/643.14
  6. Step 6: Final answer
    x = 386.57

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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.