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Finding the Fourth Proportional to 285.21, 428.12 and 192.39

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Solution

The fourth proportional to 285.21, 428.12 and 192.39 is: 288.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.21 : 428.12 = 192.39 : x
  2. Step 2: Convert to fraction form
    285.21/428.12 = 192.39/x
  3. Step 3: Cross multiply
    285.21x = 428.12 × 192.39
  4. Step 4: Simplify right side
    285.21x = 82,365.04
  5. Step 5: Solve for x
    x = 82,365.04/285.21
  6. Step 6: Final answer
    x = 288.79

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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.