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Finding the Fourth Proportional to 419.78, 578.81 and 331.29

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Solution

The fourth proportional to 419.78, 578.81 and 331.29 is: 456.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.78 : 578.81 = 331.29 : x
  2. Step 2: Convert to fraction form
    419.78/578.81 = 331.29/x
  3. Step 3: Cross multiply
    419.78x = 578.81 × 331.29
  4. Step 4: Simplify right side
    419.78x = 191,754.79
  5. Step 5: Solve for x
    x = 191,754.79/419.78
  6. Step 6: Final answer
    x = 456.80

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.