Suppose that a, b, c, d are four consecutive positive integers with a lt;b lt;c lt;d. The value of (a+d)−(b+c) is
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Solution
Since a, b, c, d are four consecutive positive integers, then b=a+1, c=a+2, and d=a+3. Thus the value of (a+d)−(b+c)=(a+a+3)−(a+1+a+2)=(2a+3)−(2a+3)=0.
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