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Finding the Fourth Proportional to 665.82, 919.38 and 489.76

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Solution

The fourth proportional to 665.82, 919.38 and 489.76 is: 676.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.82 : 919.38 = 489.76 : x
  2. Step 2: Convert to fraction form
    665.82/919.38 = 489.76/x
  3. Step 3: Cross multiply
    665.82x = 919.38 × 489.76
  4. Step 4: Simplify right side
    665.82x = 450,275.55
  5. Step 5: Solve for x
    x = 450,275.55/665.82
  6. Step 6: Final answer
    x = 676.27

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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.