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Finding the Fourth Proportional to 319.38, 440.38 and 208.70

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Solution

The fourth proportional to 319.38, 440.38 and 208.70 is: 287.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    319.38 : 440.38 = 208.70 : x
  2. Step 2: Convert to fraction form
    319.38/440.38 = 208.70/x
  3. Step 3: Cross multiply
    319.38x = 440.38 × 208.70
  4. Step 4: Simplify right side
    319.38x = 91,907.31
  5. Step 5: Solve for x
    x = 91,907.31/319.38
  6. Step 6: Final answer
    x = 287.77

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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.