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Finding the Fourth Proportional to 643.90, 888.56 and 349.16

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Solution

The fourth proportional to 643.90, 888.56 and 349.16 is: 481.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.90 : 888.56 = 349.16 : x
  2. Step 2: Convert to fraction form
    643.90/888.56 = 349.16/x
  3. Step 3: Cross multiply
    643.90x = 888.56 × 349.16
  4. Step 4: Simplify right side
    643.90x = 310,249.24
  5. Step 5: Solve for x
    x = 310,249.24/643.90
  6. Step 6: Final answer
    x = 481.83

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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.