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Finding the Fourth Proportional to 609.82, 840.81 and 491.92

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Solution

The fourth proportional to 609.82, 840.81 and 491.92 is: 678.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    609.82 : 840.81 = 491.92 : x
  2. Step 2: Convert to fraction form
    609.82/840.81 = 491.92/x
  3. Step 3: Cross multiply
    609.82x = 840.81 × 491.92
  4. Step 4: Simplify right side
    609.82x = 413,611.26
  5. Step 5: Solve for x
    x = 413,611.26/609.82
  6. Step 6: Final answer
    x = 678.25

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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.