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44 votes
44 votes
Lisa and Beverly have $20 to spend on an afternoon snack at Bob's Burger Joint. They can buy 2 hamburgers and one soda and get $1 back. Or they can buy 1 hamburger and 2 sodas and get $3 back. How much does a soda cost?

WILL MARK BRAINLIAST

User Lucas Renan
by
2.5k points

1 Answer

13 votes
13 votes

Answer:

$5

Explanation:

Use simultaneous equations to solve this.

Hamburger = H, Soda = S

Eqn. 1: 2H + 1S = $20 - $1

Eqn. 2: 1H + 2S = $20 - $3

From Eqn. 2:

1H + 2S = $17

1H = $17 - 2S (Eqn. 3)

Substitute Eqn. 3 into Eqn. 1:

2H + 1S = $19

2($17 - 2S) + 1S = $19

$34 - 4S + 1S = $19

Rearrange it to put S on one side, and the $ on the other side:

$34 - $19 = 3S

$15 = 3S

S = $15/3

S = $5

User Matesio
by
2.5k points