Alex stocks up for winter. He buys 36 cans of vegetables. He pays 80 cents per can for tomatoes and 40 cents per can for corn, for a total cost of $20.8. How many cans of corn does he buy?

Let the number of tomato cans be x, and the number of corn cans be y. We can then set up a system of equations to solve this problem.

x+y=36

0.8x+0.4y=20.8

Lets rearrange the first equation to find the value of one variable.

x=36-y

We can then substitute this value into the other equation, and solve for y.

0.8 (36-y) + 0.4y=20.8

28.8-0.8y+0.4y=20.8

-0.4y=-8

0.4y=8

y=20

Lastly, we can take this value and plug into the first equation to find the value of the other variable.

x+20=36

x=16

Thus, he bought 16 cans of tomatos and 20 cans of corn.

Alex bought 20 cans of corn and 16 cans of tomatoes.