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Finding the Fourth Proportional to 290.85, 401.39 and 203.55

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Solution

The fourth proportional to 290.85, 401.39 and 203.55 is: 280.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.85 : 401.39 = 203.55 : x
  2. Step 2: Convert to fraction form
    290.85/401.39 = 203.55/x
  3. Step 3: Cross multiply
    290.85x = 401.39 × 203.55
  4. Step 4: Simplify right side
    290.85x = 81,702.93
  5. Step 5: Solve for x
    x = 81,702.93/290.85
  6. Step 6: Final answer
    x = 280.91

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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.