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Finding the Fourth Proportional to 640.14, 959.39 and 311.15

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Solution

The fourth proportional to 640.14, 959.39 and 311.15 is: 466.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.14 : 959.39 = 311.15 : x
  2. Step 2: Convert to fraction form
    640.14/959.39 = 311.15/x
  3. Step 3: Cross multiply
    640.14x = 959.39 × 311.15
  4. Step 4: Simplify right side
    640.14x = 298,514.38
  5. Step 5: Solve for x
    x = 298,514.38/640.14
  6. Step 6: Final answer
    x = 466.33

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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.