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Finding the Fourth Proportional to 665.72, 997.05 and 319.29

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Solution

The fourth proportional to 665.72, 997.05 and 319.29 is: 478.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.72 : 997.05 = 319.29 : x
  2. Step 2: Convert to fraction form
    665.72/997.05 = 319.29/x
  3. Step 3: Cross multiply
    665.72x = 997.05 × 319.29
  4. Step 4: Simplify right side
    665.72x = 318,346.50
  5. Step 5: Solve for x
    x = 318,346.50/665.72
  6. Step 6: Final answer
    x = 478.20

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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.