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Finding the Fourth Proportional to 438.20, 604.80 and 320.60

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Solution

The fourth proportional to 438.20, 604.80 and 320.60 is: 442.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    438.20 : 604.80 = 320.60 : x
  2. Step 2: Convert to fraction form
    438.20/604.80 = 320.60/x
  3. Step 3: Cross multiply
    438.20x = 604.80 × 320.60
  4. Step 4: Simplify right side
    438.20x = 193,898.88
  5. Step 5: Solve for x
    x = 193,898.88/438.20
  6. Step 6: Final answer
    x = 442.49

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.