Alex stocks up for winter. He buys 36 cans of vegetable. He pays 80 cents per can for tomatoes and 40 cents per can for corn, for a total cost of $20.80. how many cans of tomatoes does he buy?

1 Answer
Alan P.
Sep 24, 2015

16 cans of tomatoes and 20 cans of corn

Explanation:

Define:
#color(white)("XXXX")t = # number of cans of tomatoes
#color(white)("XXXX")c = # number of cans of corn

We are told
[1]#color(white)("XXXX")t+c = 36#
[2]#color(white)("XXXX")80t+40c =2080#
Note that [2] can be simplified (by dividing by 40) to give
[3]#color(white)("XXXX")2t+c= 52#

Subtracting [1] from [3]
[4]#color(white)("XXXX")t=16#

Substituting #16# for #t# in [1]
[5]#color(white)("XXXX")16+c=36#
#rarr#[6]#color(white)("XX")c=20#

(P.S. can you tell me where Alex is buying his canned vegetables? I haven't been able to find any this cheap for decades.)

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