SOLUTION: I'm working on my exam review and I can't figure out how to do this question. The question is: a trolley loaded with 6 small cans of paint has a mass of 15.7kg. When 5 more cans ar

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: I'm working on my exam review and I can't figure out how to do this question. The question is: a trolley loaded with 6 small cans of paint has a mass of 15.7kg. When 5 more cans ar      Log On


   

Question 622124: I'm working on my exam review and I can't figure out how to do this question. The question is: a trolley loaded with 6 small cans of paint has a mass of 15.7kg. When 5 more cans are added, the mass becomes 21,7kg. Let M kilograms represent the mass of the trolley and n kilograms the mass of a small can of paint. Determine the mass of a small can of paint and the mass of the trolley. In order to solve this I need to use substitution or elimination.
Answer by vleith(2983) About Me  (Show Source):
You can put this solution on YOUR website!
M+%2B+6n+=+15.7
M+%2B+11n+=+21.7 subtract these two
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+-5n+=+-+6
n+=+6%2F5
Now use that value of n in the first equation to solve for M
M+%2B+6%2A%286%2F5%29+=+15.7
M+=+15.7+-+36%2F5
M+=+15.7+-+8.4
M+=+7.3
You can check your answer by using M and n in second equation to ee if the result is 21.7