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Finding the Fourth Proportional to 254.28, 380.78 and 239.70

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Solution

The fourth proportional to 254.28, 380.78 and 239.70 is: 358.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    254.28 : 380.78 = 239.70 : x
  2. Step 2: Convert to fraction form
    254.28/380.78 = 239.70/x
  3. Step 3: Cross multiply
    254.28x = 380.78 × 239.70
  4. Step 4: Simplify right side
    254.28x = 91,272.97
  5. Step 5: Solve for x
    x = 91,272.97/254.28
  6. Step 6: Final answer
    x = 358.95

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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.