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Finding the Fourth Proportional to 639.30, 959.14 and 331.37

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Solution

The fourth proportional to 639.30, 959.14 and 331.37 is: 497.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.30 : 959.14 = 331.37 : x
  2. Step 2: Convert to fraction form
    639.30/959.14 = 331.37/x
  3. Step 3: Cross multiply
    639.30x = 959.14 × 331.37
  4. Step 4: Simplify right side
    639.30x = 317,830.22
  5. Step 5: Solve for x
    x = 317,830.22/639.30
  6. Step 6: Final answer
    x = 497.15

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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.