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Finding the Fourth Proportional to 419.85, 579.68 and 321.43

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Solution

The fourth proportional to 419.85, 579.68 and 321.43 is: 443.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.85 : 579.68 = 321.43 : x
  2. Step 2: Convert to fraction form
    419.85/579.68 = 321.43/x
  3. Step 3: Cross multiply
    419.85x = 579.68 × 321.43
  4. Step 4: Simplify right side
    419.85x = 186,326.54
  5. Step 5: Solve for x
    x = 186,326.54/419.85
  6. Step 6: Final answer
    x = 443.79

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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.