Manuel bought 6 candy bars and 3 sodas at the gas station for $8.40. Gary bought 3 candy bars and 4 sodas at the same gas station for $7.45. What is the price of one soda?

Question

need help with this question dont understand this question thank you need this solved today

Answer 1

Hi Geovanni,

Set a variable for candy bars and sodas, say C for the price of the candy bars and S for the price of the sodas.

Set up two equations.

6C + 3S = 8.40

3C + 4S = 7.45

Can you now solve these two equations to find S the price of the soda?

Let me know if you have any more questions.

Miss Julie

www.wyzant.com/tutors/missjulie

Answer 2

Manuel bought 6 candy bars and 3 sodas at the gas station for $8.40. Gary bought 3 candy bars and 4 sodas at the same gas station for $7.45. What is the price of one soda?

--------Let variables represent the unknown values-------

let c = price of candy bars

let s = price of sodas

-------Now use the variables and translate the word problem into math equations like so---------

6c + 3s = 8.40

3c + 4s = 7.45

----------------You now have the very common situation of 2 equations and 2 unknowns-----------solve using various methods--------------

1. isolate one of the variables and then
2. substitute that variable into one of the equations to solve

3c + 4s = 7.45

-3c -3c..........subtract 3c from both sides.....

4s = 7.45 - 3c

/4 /4 ............divide both sides by 4

s = (7.45 - 3c)/4........we now have the s variable isolated......substitute it into first equation like so....

6c + 3 ((7.45-3c)/4) = 8.40

24c + 22.35 - 9c = 33.60.......multiply both sides by 4........helps remove fractional part of equation....

15c = 33.60 - 22.35

15c = 11.25......c = .75....price of candy bar is 75 cents.....s = (7.45 - 3(.75))/4 = $1.30 ... soda is $1.30

....check....your answers...

3c + 4s = 7.45.......3 (.75) + 4 (1.30) = 2.25 + 5.20 = 7.45.....that checks out perfectly......

6c + 3s = 8.40.......6 (.75) + 3 (1.30) = 4.50 + 3.90 = 8.40....checks out......