Question
At a concession stand, seven hot dogs and two hamburgers cost $11.00, two hot dogs and seven hamburgers cost $16.00. Find the cost of one hot dog and the cost of one hamburger.
Answers
Steve
7d+2b = 11
2d+7b = 16
5d + 2(d+b) = 11
5b + 2(d+b) = 16
add the equations and you get
5(d+b) + 4(d+b) = 27
9(d+b) = 27
d+b = 3
similarly, b-d = 1
b=2
d=1
dog costs $1
burger costs $2
2d+7b = 16
5d + 2(d+b) = 11
5b + 2(d+b) = 16
add the equations and you get
5(d+b) + 4(d+b) = 27
9(d+b) = 27
d+b = 3
similarly, b-d = 1
b=2
d=1
dog costs $1
burger costs $2