At the corner store, Nico bought 5 pencils for $0.10 each and 3 pens for $0.50 each. He used t to represent the sales tax, in dollars, that he also paid. He paid a total of $2.12, including tax.
Nico wrote this equation to represent what he paid. What errors, if any, did he make?
5(0.10) + 3(0.50) - t = 2.12
He should have multiplied 0.10 by 3 instead of 5.
He should have multiplied 0.50 by 5 instead of 3.
He should have added t instead of subtracting t.
He should have multiplied by t instead of subtracting t.