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Finding the Fourth Proportional to 285.76, 428.70 and 204.40

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Solution

The fourth proportional to 285.76, 428.70 and 204.40 is: 306.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.76 : 428.70 = 204.40 : x
  2. Step 2: Convert to fraction form
    285.76/428.70 = 204.40/x
  3. Step 3: Cross multiply
    285.76x = 428.70 × 204.40
  4. Step 4: Simplify right side
    285.76x = 87,626.28
  5. Step 5: Solve for x
    x = 87,626.28/285.76
  6. Step 6: Final answer
    x = 306.64

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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.