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Harry bought 2 mints and 5 apples for $2.36. Craig bought 4 mints and 3 apples for $1.78.Find the cost of a mint and the cost of an apple.

User Tehvan
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1 Answer

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Harry bought 2 mints and 5 apples for $2.36

Craig bought 4 mints and 3 apples for $1.78

firstly, let x represent the number of mints and let y represent the number of apples

For Harry

2 * x + 5 * y = 2.36

2x + 5y = 2.36 -------- equation 1

For Craig

4 * x + 3 * y = 1.78

4x + 3y = 1.78 --------- equation 2

2x + 5y = 2.36

4x + 3y = 1.78

These two equations can be solve simultaneously and we will be using the elimination method.

Let us eliminate x first

To eliminate x, we will mulitply 2 by equation 1 and 1by equation 2

2x * 2 + 5y * 2 = 2.36 x 2

4x * 1 + 3y * 1 = 1.78 x 1

4x + 10y = 4.72 ----- equation 3

4x + 3y = 1.78 -------- equation 4

substract equation 4 from equation 3

4x - 4x + 10y - 3y = 4.72 - 1.78

0 + 7y = 2.94

7y = 2.94

divide both sides by 7

7y/7 = 2.94/7

y = 0.42

To find x, substitute y = 0.42 in equation 1

2x + 5y = 2.36

2x + 5(0.42) = 2.36

2x + 2.1 = 2.36

make 2x the subject of the formula

2x = 2.36 - 2.1

2x = 0.26

divide both sides by 2

2x/2 = 0.26/2

x = 0.13

since x = mint and y = apples

The cost for a mint is $0.13 and the cost for an apple is $0.42

User Alex Lew
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