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Finding the Fourth Proportional to 639.49, 958.70 and 254.53

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Solution

The fourth proportional to 639.49, 958.70 and 254.53 is: 381.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.49 : 958.70 = 254.53 : x
  2. Step 2: Convert to fraction form
    639.49/958.70 = 254.53/x
  3. Step 3: Cross multiply
    639.49x = 958.70 × 254.53
  4. Step 4: Simplify right side
    639.49x = 244,016.64
  5. Step 5: Solve for x
    x = 244,016.64/639.49
  6. Step 6: Final answer
    x = 381.58

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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.