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Finding the Fourth Proportional to 639.89, 959.97 and 347.38

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Solution

The fourth proportional to 639.89, 959.97 and 347.38 is: 521.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.89 : 959.97 = 347.38 : x
  2. Step 2: Convert to fraction form
    639.89/959.97 = 347.38/x
  3. Step 3: Cross multiply
    639.89x = 959.97 × 347.38
  4. Step 4: Simplify right side
    639.89x = 333,474.38
  5. Step 5: Solve for x
    x = 333,474.38/639.89
  6. Step 6: Final answer
    x = 521.14

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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.