Pilar wanted to use estimation to solve a decimal addition problem. she correctly used estimation to rewrite the problem as 12 + 3 + 5 + 6. what could her original problem have been?

Hello I don’t rly know the answer but I would love to help

X= 2 he can buy 2 packs of cards for $12 and an action figure for $3 so he would spend $15 in total plus the free poster

This is what i found “an explicit formula designates the nth term of the sequence, as an expression of n (where n = the term's location). it defines the sequence as a formula in terms of n. this example is an arithmetic sequence(the same number, 5, is added to each term to get to the next term).” i hope this you for what your looking for. can you plz mark me brainliest?