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Finding the Fourth Proportional to 665.96, 999.10 and 319.20

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Solution

The fourth proportional to 665.96, 999.10 and 319.20 is: 478.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.96 : 999.10 = 319.20 : x
  2. Step 2: Convert to fraction form
    665.96/999.10 = 319.20/x
  3. Step 3: Cross multiply
    665.96x = 999.10 × 319.20
  4. Step 4: Simplify right side
    665.96x = 318,912.72
  5. Step 5: Solve for x
    x = 318,912.72/665.96
  6. Step 6: Final answer
    x = 478.88

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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.