The lawton family spent a total of 26.75 on lunch. They bought 5 drinks and 3 sandwiches. Each drink costs $2.50 less than a sandwich. How do you find the cost of each sandwich?

1 Answer
Oct 27, 2016

The result makes no sense in the real world but according to the supplied values a sandwich costs #$4.90 58#
(Possibly the total bill should have been $#26.70# (???))

Explanation:

Let
#color(white)("XXX")d# represent the cost of a drink, and
#color(white)("XXX")s# represent the cost of a sandwich.

We are told
[1]#color(white)("XXX")5d+3s=26.75#
and
[1]#color(white)("XXX")d=s-2.50#

Using [2] we can replace #d# with #(s-2.50)# in [1] to get
#color(white)("XXX")5(s-2.50)+3s=26.75#

Simplifying
#color(white)("XXX")5s-12.50+3s=26.75#

#color(white)("XXX")8s= 39.25#

#color(white)("XXX")s=4.90 5/8#