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Finding the Fourth Proportional to 427.89, 641.64 and 254.60

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Solution

The fourth proportional to 427.89, 641.64 and 254.60 is: 381.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.89 : 641.64 = 254.60 : x
  2. Step 2: Convert to fraction form
    427.89/641.64 = 254.60/x
  3. Step 3: Cross multiply
    427.89x = 641.64 × 254.60
  4. Step 4: Simplify right side
    427.89x = 163,361.54
  5. Step 5: Solve for x
    x = 163,361.54/427.89
  6. Step 6: Final answer
    x = 381.78

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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.