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Finding the Fourth Proportional to 685.59, 1,027.36 and 320.28

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Solution

The fourth proportional to 685.59, 1,027.36 and 320.28 is: 479.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    685.59 : 1,027.36 = 320.28 : x
  2. Step 2: Convert to fraction form
    685.59/1,027.36 = 320.28/x
  3. Step 3: Cross multiply
    685.59x = 1,027.36 × 320.28
  4. Step 4: Simplify right side
    685.59x = 329,042.86
  5. Step 5: Solve for x
    x = 329,042.86/685.59
  6. Step 6: Final answer
    x = 479.94

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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.