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Finding the Fourth Proportional to 383.20, 528.82 and 208.55

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Solution

The fourth proportional to 383.20, 528.82 and 208.55 is: 287.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    383.20 : 528.82 = 208.55 : x
  2. Step 2: Convert to fraction form
    383.20/528.82 = 208.55/x
  3. Step 3: Cross multiply
    383.20x = 528.82 × 208.55
  4. Step 4: Simplify right side
    383.20x = 110,286.21
  5. Step 5: Solve for x
    x = 110,286.21/383.20
  6. Step 6: Final answer
    x = 287.81

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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.