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Finding the Fourth Proportional to 643.14, 886.14 and 640.44

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Solution

The fourth proportional to 643.14, 886.14 and 640.44 is: 882.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.14 : 886.14 = 640.44 : x
  2. Step 2: Convert to fraction form
    643.14/886.14 = 640.44/x
  3. Step 3: Cross multiply
    643.14x = 886.14 × 640.44
  4. Step 4: Simplify right side
    643.14x = 567,519.50
  5. Step 5: Solve for x
    x = 567,519.50/643.14
  6. Step 6: Final answer
    x = 882.42

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.