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Finding the Fourth Proportional to 380.99, 571.89 and 285.41

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Solution

The fourth proportional to 380.99, 571.89 and 285.41 is: 428.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    380.99 : 571.89 = 285.41 : x
  2. Step 2: Convert to fraction form
    380.99/571.89 = 285.41/x
  3. Step 3: Cross multiply
    380.99x = 571.89 × 285.41
  4. Step 4: Simplify right side
    380.99x = 163,220.27
  5. Step 5: Solve for x
    x = 163,220.27/380.99
  6. Step 6: Final answer
    x = 428.42

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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.