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Finding the Fourth Proportional to 285.58, 428.79 and 204.85

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Solution

The fourth proportional to 285.58, 428.79 and 204.85 is: 307.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.58 : 428.79 = 204.85 : x
  2. Step 2: Convert to fraction form
    285.58/428.79 = 204.85/x
  3. Step 3: Cross multiply
    285.58x = 428.79 × 204.85
  4. Step 4: Simplify right side
    285.58x = 87,837.63
  5. Step 5: Solve for x
    x = 87,837.63/285.58
  6. Step 6: Final answer
    x = 307.58

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.