Andrew and Cutter were assigned to buy refreshments for the History Club meeting
ID: 3120402 • Letter: A
Question
Explanation / Answer
Solution: Let price of six pack drinks = x,
price of bags of chips = y and
price of packages of cookies = z
now according to the problem the equations are
3x+2y+4z=22---- 1
2x+4y+5z=26.30 ------2
and
x+2y+4z=17.20 -------3
Now subtracting 3 from 1
i.e. 3x+2y+4z-(x+2y+4z) = 22-17.20
3x+2y+4z-x-2y-4z = 4.8
2x = 4.8
x = 2.4
now put x = 2.4 in equation 1 and 2
so equation 1 - -> 3x+2y+4z = 22
3(2.4)+2y+4z = 22
7.2+2y+4z = 22
2y + 4z = 14.8 ---4
For equation 2 - ->
2x+4y+5z=26.30
4.8+4y+5z=26.30
4y+5z=21.5---5
multiply equation 4 with number 2 we get
2(2y+4z) = 59.2
4y+8z = 29.6--6
Subtract 5 from 6
4y+8z-4y-5z=8.1
3z=8.1
z=2.7
Put this value in 5
we get
4y+5z=21.5
4y+5(2.7) = 21.5
4y+13.5=21.5
4y=8
y=2.