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Finding the Fourth Proportional to 643.39, 888.17 and 486.09

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Solution

The fourth proportional to 643.39, 888.17 and 486.09 is: 671.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.39 : 888.17 = 486.09 : x
  2. Step 2: Convert to fraction form
    643.39/888.17 = 486.09/x
  3. Step 3: Cross multiply
    643.39x = 888.17 × 486.09
  4. Step 4: Simplify right side
    643.39x = 431,730.56
  5. Step 5: Solve for x
    x = 431,730.56/643.39
  6. Step 6: Final answer
    x = 671.02

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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.