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Finding the Fourth Proportional to 285.66, 428.22 and 213.84

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Solution

The fourth proportional to 285.66, 428.22 and 213.84 is: 320.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.66 : 428.22 = 213.84 : x
  2. Step 2: Convert to fraction form
    285.66/428.22 = 213.84/x
  3. Step 3: Cross multiply
    285.66x = 428.22 × 213.84
  4. Step 4: Simplify right side
    285.66x = 91,570.56
  5. Step 5: Solve for x
    x = 91,570.56/285.66
  6. Step 6: Final answer
    x = 320.56

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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.