SOLUTION: Sally bought three chocolate bars and a pack of gum and paid $1.75. Jake bought two chocolate bars and four packs of gum and paid $2.00. Find the cost of a chocolate bar and the

Algebra ->  Graphs -> SOLUTION: Sally bought three chocolate bars and a pack of gum and paid $1.75. Jake bought two chocolate bars and four packs of gum and paid $2.00. Find the cost of a chocolate bar and the       Log On


   

Question 110542: Sally bought three chocolate bars and a pack of gum and paid $1.75. Jake bought two chocolate bars and four packs of gum and paid $2.00. Find the cost of a chocolate bar and the cost of a pack of gum
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Let call the cost of the chocalate bar C.
Let's call the cost of a pack of gum G.
From Sally,
1.3C%2BG=1.75
From Jake,
2.2C%2B4G=2.00
Let's use equation 1 to solve for G in terms of C.
1.3C%2BG=1.75
3C-3C%2BG=1.75-3C Subtract 3C from both sides
G=1.75-3C
Now substitute this value into equation 2.
2.2C%2B4G=2.00
2C%2B4%281.75-3C%29=2.00
2C%2B7-12C=2.00
7-7-10C=2.00-7
-10C=-5
C=-5%2F-10
C=0.50
From above,
G=1.75-3C
G=1.75-3%280.50%29
G=0.25
So the chocolate costs $0.50 and the gum cost $0.25.
Check your answers.
1.3C%2BG=1.75
3%280.50%29%2B0.25=1.75
1.75=1.75
True statement.
2.2C%2B4G=2.00
2%280.50%29%2B4%280.25%29=2.00
2.00=2.00
True statement.
Both answers lead to true statements.
Good answers.