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Finding the Fourth Proportional to 319.38, 440.40 and 208.65

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Solution

The fourth proportional to 319.38, 440.40 and 208.65 is: 287.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    319.38 : 440.40 = 208.65 : x
  2. Step 2: Convert to fraction form
    319.38/440.40 = 208.65/x
  3. Step 3: Cross multiply
    319.38x = 440.40 × 208.65
  4. Step 4: Simplify right side
    319.38x = 91,889.46
  5. Step 5: Solve for x
    x = 91,889.46/319.38
  6. Step 6: Final answer
    x = 287.71

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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.