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Finding the Fourth Proportional to 285.66, 428.76 and 278.98

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Solution

The fourth proportional to 285.66, 428.76 and 278.98 is: 418.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.66 : 428.76 = 278.98 : x
  2. Step 2: Convert to fraction form
    285.66/428.76 = 278.98/x
  3. Step 3: Cross multiply
    285.66x = 428.76 × 278.98
  4. Step 4: Simplify right side
    285.66x = 119,614.39
  5. Step 5: Solve for x
    x = 119,614.39/285.66
  6. Step 6: Final answer
    x = 418.73

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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.