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Finding the Fourth Proportional to 639.88, 960.05 and 249.86

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Solution

The fourth proportional to 639.88, 960.05 and 249.86 is: 374.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.88 : 960.05 = 249.86 : x
  2. Step 2: Convert to fraction form
    639.88/960.05 = 249.86/x
  3. Step 3: Cross multiply
    639.88x = 960.05 × 249.86
  4. Step 4: Simplify right side
    639.88x = 239,881.12
  5. Step 5: Solve for x
    x = 239,881.12/639.88
  6. Step 6: Final answer
    x = 374.89

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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.