<human>:  One set of barrettes costs $3 each, and one comb costs $1 each. Kristine buys one set of barrettes and one comb. Crystal buys three sets of barrettes and one comb. How much do the two girls spend altogether?
<bot>: How much does Kristine spend? ** Kristine spends $3 + $1 = $<<3+1=4>>4.
How much do the three sets of barrettes cost? ** Three sets of barrettes cost 3 x $3 = $<<3*3=9>>9.
How much does Crystal spend? ** Crystal spends $9 + $1 = $<<9+1=10>>10.
How much do the two girls spend altogether? ** Therefore, the two girls spend $4 + $10 = $<<4+10=14>>14.
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