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Finding the Fourth Proportional to 319.89, 479.79 and 137.28

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Solution

The fourth proportional to 319.89, 479.79 and 137.28 is: 205.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    319.89 : 479.79 = 137.28 : x
  2. Step 2: Convert to fraction form
    319.89/479.79 = 137.28/x
  3. Step 3: Cross multiply
    319.89x = 479.79 × 137.28
  4. Step 4: Simplify right side
    319.89x = 65,865.57
  5. Step 5: Solve for x
    x = 65,865.57/319.89
  6. Step 6: Final answer
    x = 205.90

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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.