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Finding the Fourth Proportional to 665.29, 997.39 and 408.25

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Solution

The fourth proportional to 665.29, 997.39 and 408.25 is: 612.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.29 : 997.39 = 408.25 : x
  2. Step 2: Convert to fraction form
    665.29/997.39 = 408.25/x
  3. Step 3: Cross multiply
    665.29x = 997.39 × 408.25
  4. Step 4: Simplify right side
    665.29x = 407,184.47
  5. Step 5: Solve for x
    x = 407,184.47/665.29
  6. Step 6: Final answer
    x = 612.04

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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.