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Finding the Fourth Proportional to 285.82, 428.84 and 207.81

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Solution

The fourth proportional to 285.82, 428.84 and 207.81 is: 311.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.82 : 428.84 = 207.81 : x
  2. Step 2: Convert to fraction form
    285.82/428.84 = 207.81/x
  3. Step 3: Cross multiply
    285.82x = 428.84 × 207.81
  4. Step 4: Simplify right side
    285.82x = 89,117.24
  5. Step 5: Solve for x
    x = 89,117.24/285.82
  6. Step 6: Final answer
    x = 311.79

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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.