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i wnet to the grocery store this weekend and bought 3 lbs of apples and 4lbs of oranges for $3.45. if i had bought 4 lbs of apples and 2 lbs of oranges then it would of only cost me $3.10. how much did it cost me per pound for apples and how much per pound of oranges?

1 Answer

5 votes

Answer:

apples - $0,55 per pound

oranges - $0,45 per pound

Explanation:

Let's assume, that apples cost x dollars per pound and oranges cost y dollars per pound.

Let's write 2 equations according to the given information and put them in a system:

{3x + 4y = 3,45,

{4x + 2y = 3,10;

Let's make x the subject from the 1st equation:

3x = 3,45 - 4y / : 3

x = 1,15 - 1 1/3y

Let's replace x in the 2nd equation:


4 *(1.15 - 1 (1)/(3) y) + 2y = 3.10


4.6 - (16)/(3) y + 2y = 3.10


- (10)/(3) y = 3.10- 4.6


- (10)/(3) y = - 1.5


y = 0.45


x = 1.15 - 1 (1)/(3) * 0.45 = 0.55

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