Question

You bought 5 chocolate bars and 8 blow pops for $23.25. Your sister bought 2 chocolate bars and 13 blow pops for $21.55. How much did each chocolate

bar cost? Each chocolate bar cost?

Answer 1

Cost of each chocolate bar = $2.65

Cost of each blow pop = $1.25

Explanation:

Let x = Cost of chocolate bar

y= Cost of blow pops

We can make system of equations and find value of x and y

You bought 5 chocolate bars and 8 blow pops for $23.25.
`5x+8y=23.25`

Your sister bought 2 chocolate bars and 13 blow pops for $21.55.
`2x+13y=21.55`

Let:

`5x+8y=23.25--eq(1)\\2x+13y=--eq(2)`

Multiply eq(1) with 2 and eq(2) with 5 and subtract

`10x+16y=46.5\\10x+65y=107.75\\- \ \ \ - \ \ \ \ \ \ - \\------\\-49y=-61.25\\y=(-61.25)/(-49) \\y=1.25`

So, value of y = 1.25

Putting value of y in eq(1) to find value of x

`5x+8y=23.25\\5x+8(1.25)=23.25\\5x+10=23.25\\5x=23.25-10\\5x=13.25\\x=13.25/5\\x=2.65`

Value of x = 2.65

So, Cost of each chocolate bar = x = $2.65

Cost of each blow pop = y = $1.25