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Finding the Fourth Proportional to 319.09, 440.31 and 208.39

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Solution

The fourth proportional to 319.09, 440.31 and 208.39 is: 287.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    319.09 : 440.31 = 208.39 : x
  2. Step 2: Convert to fraction form
    319.09/440.31 = 208.39/x
  3. Step 3: Cross multiply
    319.09x = 440.31 × 208.39
  4. Step 4: Simplify right side
    319.09x = 91,756.20
  5. Step 5: Solve for x
    x = 91,756.20/319.09
  6. Step 6: Final answer
    x = 287.56

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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.