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Finding the Fourth Proportional to 609.20, 912.60 and 320

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Solution

The fourth proportional to 609.20, 912.60 and 320 is: 479.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    609.20 : 912.60 = 320 : x
  2. Step 2: Convert to fraction form
    609.20/912.60 = 320/x
  3. Step 3: Cross multiply
    609.20x = 912.60 × 320
  4. Step 4: Simplify right side
    609.20x = 292,032
  5. Step 5: Solve for x
    x = 292,032/609.20
  6. Step 6: Final answer
    x = 479.37

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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.