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Finding the Fourth Proportional to 427.85, 641.77 and 330.49

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Solution

The fourth proportional to 427.85, 641.77 and 330.49 is: 495.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.85 : 641.77 = 330.49 : x
  2. Step 2: Convert to fraction form
    427.85/641.77 = 330.49/x
  3. Step 3: Cross multiply
    427.85x = 641.77 × 330.49
  4. Step 4: Simplify right side
    427.85x = 212,096.14
  5. Step 5: Solve for x
    x = 212,096.14/427.85
  6. Step 6: Final answer
    x = 495.73

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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.