Jan buys 4 candy bars and 2 sodas for $4.80. Tom buys 3 candy bars and 4 sodas for $6.10. How much is a candy bar and how much is a soda?

Question

Answer w/ work please.

Answer 1

1) Set up expressions for each person's purchases.

 

4c + 2s = 4.80

3c + 4s =6.10

 

2) Let's isolate a variable by subtracting the 2 expressions.

 

c - 2s = -1.30

c = -1.3 + 2s

 

3) Now let's plug that into equation 1.

 

4(-1.3 + 2s) + 2s = 4.80

-5.2 + 8s + 2s =4.8

10s = 10

s = 1

 

4) Now solve for c.

 

c = -1.3 + 2(1)

c = -1.3 + 2

c = .7

 

5) Check your work by plugging them back into the originals.

 

4(.7) + 2(1) = 4.80

2.8 + 2 = 4.8

4.8=4.8

3(.7) + 4(1) =6.10

2.1 + 4 = 6.1

6.1 = 6.1