you buy 5 packages of hot dogs and hamburgers for a cookout. hot dogs cost $2.20 and hamburgers cost $5.20. you spend $20. how many of each can you buy?

Question

set up for a system of equations 

Answer 1

Let h = number of hot dog packs

Let b = number of burger packs

 

we buy 5 total packs so:

h + b = 5

 

hotdogs cost $2.20, burgers cost $5.20

2.2h + 5.2b = 20

 

from 1st equation, h = 5-b

Substitute that into 2nd equation

 

2.2(5-b) + 5.2b = 20

11 - 2.2b + 5.2b = 20

11 + 3b = 20

3b = 9

b = 3

 

He bought 3 packs of burgers and 2 packs of hotdogs.