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Finding the Fourth Proportional to 639.79, 959.69 and 249.75

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Solution

The fourth proportional to 639.79, 959.69 and 249.75 is: 374.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.79 : 959.69 = 249.75 : x
  2. Step 2: Convert to fraction form
    639.79/959.69 = 249.75/x
  3. Step 3: Cross multiply
    639.79x = 959.69 × 249.75
  4. Step 4: Simplify right side
    639.79x = 239,682.58
  5. Step 5: Solve for x
    x = 239,682.58/639.79
  6. Step 6: Final answer
    x = 374.63

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Similar ratio
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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.