From selling his shirts, Kekai makes 5 * $1 = $<<5*1=5>>5
From selling his pants, Kekai makes 5 * $3 = $<<5*3=15>>15
The total amount of money Kekai earns is $5 + $15 = $<<5+15=20>>20
Since Kekai gives half of the money to his parents, he has $20 / 2 = $<<20/2=10>>10 left
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