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Finding the Fourth Proportional to 639.09, 958.67 and 330.75

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Solution

The fourth proportional to 639.09, 958.67 and 330.75 is: 496.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.09 : 958.67 = 330.75 : x
  2. Step 2: Convert to fraction form
    639.09/958.67 = 330.75/x
  3. Step 3: Cross multiply
    639.09x = 958.67 × 330.75
  4. Step 4: Simplify right side
    639.09x = 317,078.45
  5. Step 5: Solve for x
    x = 317,078.45/639.09
  6. Step 6: Final answer
    x = 496.14

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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.