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Finding the Fourth Proportional to 285.80, 428.99 and 251.78

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Solution

The fourth proportional to 285.80, 428.99 and 251.78 is: 377.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.80 : 428.99 = 251.78 : x
  2. Step 2: Convert to fraction form
    285.80/428.99 = 251.78/x
  3. Step 3: Cross multiply
    285.80x = 428.99 × 251.78
  4. Step 4: Simplify right side
    285.80x = 108,007.70
  5. Step 5: Solve for x
    x = 108,007.70/285.80
  6. Step 6: Final answer
    x = 377.92

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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.