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Finding the Fourth Proportional to 321.84, 480.87 and 285.39

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Solution

The fourth proportional to 321.84, 480.87 and 285.39 is: 426.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    321.84 : 480.87 = 285.39 : x
  2. Step 2: Convert to fraction form
    321.84/480.87 = 285.39/x
  3. Step 3: Cross multiply
    321.84x = 480.87 × 285.39
  4. Step 4: Simplify right side
    321.84x = 137,235.49
  5. Step 5: Solve for x
    x = 137,235.49/321.84
  6. Step 6: Final answer
    x = 426.41

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.