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Finding the Fourth Proportional to 320.39, 480.62 and 137.80

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Solution

The fourth proportional to 320.39, 480.62 and 137.80 is: 206.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    320.39 : 480.62 = 137.80 : x
  2. Step 2: Convert to fraction form
    320.39/480.62 = 137.80/x
  3. Step 3: Cross multiply
    320.39x = 480.62 × 137.80
  4. Step 4: Simplify right side
    320.39x = 66,229.44
  5. Step 5: Solve for x
    x = 66,229.44/320.39
  6. Step 6: Final answer
    x = 206.72

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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.