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Finding the Fourth Proportional to 679.27, 1,019.71 and 405.49

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Solution

The fourth proportional to 679.27, 1,019.71 and 405.49 is: 608.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    679.27 : 1,019.71 = 405.49 : x
  2. Step 2: Convert to fraction form
    679.27/1,019.71 = 405.49/x
  3. Step 3: Cross multiply
    679.27x = 1,019.71 × 405.49
  4. Step 4: Simplify right side
    679.27x = 413,478.64
  5. Step 5: Solve for x
    x = 413,478.64/679.27
  6. Step 6: Final answer
    x = 608.71

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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.