I NEED SOME HELP

so I give away points because why not, now you guys have some real math to do.
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Mr. piper is driving peter, roddy, and scott home from school. all of them want to ride in the front seat. how can he make a fair decision about who rides in the front seat?

100 points and 1- -12=y-36 2- x/25=-25 3- -n=40

Great freights a local shipping company, bases its charges on the weight of the items being shipped. in addition to changing 0.40$ per pound, great freights also charges a one-time fee of 10$ to set up a customers account.