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Finding the Fourth Proportional to 619.21, 853.49 and 494.65

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Solution

The fourth proportional to 619.21, 853.49 and 494.65 is: 681.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.21 : 853.49 = 494.65 : x
  2. Step 2: Convert to fraction form
    619.21/853.49 = 494.65/x
  3. Step 3: Cross multiply
    619.21x = 853.49 × 494.65
  4. Step 4: Simplify right side
    619.21x = 422,172.09
  5. Step 5: Solve for x
    x = 422,172.09/619.21
  6. Step 6: Final answer
    x = 681.80

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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.