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Finding the Fourth Proportional to 639.47, 959.19 and 200.72

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Solution

The fourth proportional to 639.47, 959.19 and 200.72 is: 301.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.47 : 959.19 = 200.72 : x
  2. Step 2: Convert to fraction form
    639.47/959.19 = 200.72/x
  3. Step 3: Cross multiply
    639.47x = 959.19 × 200.72
  4. Step 4: Simplify right side
    639.47x = 192,528.62
  5. Step 5: Solve for x
    x = 192,528.62/639.47
  6. Step 6: Final answer
    x = 301.08

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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.