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Finding the Fourth Proportional to 287.40, 396.15 and 204.38

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Solution

The fourth proportional to 287.40, 396.15 and 204.38 is: 281.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.40 : 396.15 = 204.38 : x
  2. Step 2: Convert to fraction form
    287.40/396.15 = 204.38/x
  3. Step 3: Cross multiply
    287.40x = 396.15 × 204.38
  4. Step 4: Simplify right side
    287.40x = 80,965.14
  5. Step 5: Solve for x
    x = 80,965.14/287.40
  6. Step 6: Final answer
    x = 281.72

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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.