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Question

There are 155 juniors and seniors in a college seminar. The number of seniors exceeds the number of juniors by 27. How many of each type of student are in the seminar?

Answer 1

J + S = 155

 

S = J + 27

 

Use substitution

 

Our first equation J + S = 155 becomes  J + (J + 27) = 155

 

2J + 27 = 155

 

2J = 128

 

J = 64

 

If J = 64 then S = 64+27 = 91