Question 953675
chips=c; burger=2c; pizza=4c
c+2c+4c=$21
7c=$21
c=$3
Burger=2c=2($3)=6$ ANSWER: Burgers cost $6.
CHECK 
pizza=4c=4($3)=$12
chips+burger+pizza=$21
$3+$6+$12=$21
$21=$21