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Finding the Fourth Proportional to 665.32, 997.98 and 387.76

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Solution

The fourth proportional to 665.32, 997.98 and 387.76 is: 581.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.32 : 997.98 = 387.76 : x
  2. Step 2: Convert to fraction form
    665.32/997.98 = 387.76/x
  3. Step 3: Cross multiply
    665.32x = 997.98 × 387.76
  4. Step 4: Simplify right side
    665.32x = 386,976.72
  5. Step 5: Solve for x
    x = 386,976.72/665.32
  6. Step 6: Final answer
    x = 581.64

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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.