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Algebra Difficulty 2.7 Junior Find the answer

Each of the variables a,b,c,da, b, c, d, and ee represents a positive integer with the properties that b+d>a+db+d>a+d, c+e>b+ec+e>b+e, b+d=cb+d=c, a+c=b+ea+c=b+e. Which of the variables has the greatest value?

A number or a short expression. Spacing and $ signs are ignored.

Solution

Since b+d>a+db+d>a+d, then b>ab>a. This means that aa does not have the greatest value. Since c+e>b+ec+e>b+e, then c>bc>b. This means that bb does not have the greatest value. Since b+d=cb+d=c and each of b,c,db, c, d is positive, then d<cd<c, which means that dd does not have the greatest value. Consider the last equation a+c=b+ea+c=b+e along with the fact that a<b<ca<b<c. From this, we see that e=c+(ab)e=c+(a-b). Since a<ba<b, then aba-b is negative and so e<ce<c. This means that cc has the greatest value.

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