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Finding the Fourth Proportional to 639.49, 959.30 and 200.75

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Solution

The fourth proportional to 639.49, 959.30 and 200.75 is: 301.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.49 : 959.30 = 200.75 : x
  2. Step 2: Convert to fraction form
    639.49/959.30 = 200.75/x
  3. Step 3: Cross multiply
    639.49x = 959.30 × 200.75
  4. Step 4: Simplify right side
    639.49x = 192,579.48
  5. Step 5: Solve for x
    x = 192,579.48/639.49
  6. Step 6: Final answer
    x = 301.15

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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.