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Finding the Fourth Proportional to 684.75, 1,027.05 and 319.31

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Solution

The fourth proportional to 684.75, 1,027.05 and 319.31 is: 478.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    684.75 : 1,027.05 = 319.31 : x
  2. Step 2: Convert to fraction form
    684.75/1,027.05 = 319.31/x
  3. Step 3: Cross multiply
    684.75x = 1,027.05 × 319.31
  4. Step 4: Simplify right side
    684.75x = 327,942.20
  5. Step 5: Solve for x
    x = 327,942.20/684.75
  6. Step 6: Final answer
    x = 478.92

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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.