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Finding the Fourth Proportional to 318.39, 439.40 and 208.16

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Solution

The fourth proportional to 318.39, 439.40 and 208.16 is: 287.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    318.39 : 439.40 = 208.16 : x
  2. Step 2: Convert to fraction form
    318.39/439.40 = 208.16/x
  3. Step 3: Cross multiply
    318.39x = 439.40 × 208.16
  4. Step 4: Simplify right side
    318.39x = 91,464.46
  5. Step 5: Solve for x
    x = 91,464.46/318.39
  6. Step 6: Final answer
    x = 287.27

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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.