Question 1018032
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S=streamers; H=hats
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2S+4H=$11
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3S+15H=$30 . Multiply by 2/3
2S+10H=$20 . Subtract first equation
2S+4H=$11
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6H=$9
H=$1.50
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2S+4H=$11
2S+4($1.50)=$11
2S+$6=$11
2S=$5
S=$2.50
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ANSWER: Hats cost $1.50 and streamers cost $2.50.
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CHECK:
3S+15H=$30
3($2.50)+15($1.50)=$30
$7.50+$22.50=$30
$30=$30
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