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Finding the Fourth Proportional to 640.21, 960.08 and 249.89

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Solution

The fourth proportional to 640.21, 960.08 and 249.89 is: 374.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.21 : 960.08 = 249.89 : x
  2. Step 2: Convert to fraction form
    640.21/960.08 = 249.89/x
  3. Step 3: Cross multiply
    640.21x = 960.08 × 249.89
  4. Step 4: Simplify right side
    640.21x = 239,911.94
  5. Step 5: Solve for x
    x = 239,911.94/640.21
  6. Step 6: Final answer
    x = 374.74

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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.