Question

Kaylin bought a soda and two bags of popcorn for $3.00 . HER brother bought three sodas and a bag of popcorn for $6.50

Answer 1

Answer: price of soda (a) = $2 and price of popcorn (b) = $0.5

Step-by-step explanation:

Let's denote soda = a and popcorn = b

Kaylin bought a soda and two popcorn, writing out an equation for this would be

a + 2b = $3...........equation (i)

And her brother bought 3 sodas and 1 popcorn.

3a + b = $6.50..........equation (ii)

From equation (i),

a + 2b = 3

Making a the subject of formula,

a = 3 - 2b......equation (iii)

Using substitution reaction, put equation (iii) into equation (ii)

3(3 - 2b) + b = $6.50

9 - 6b + b = 6.50

9 - 5b = 6.50

Collecting like terms,

5b = 9 - 6.50

Divide both sides by 5,

b = 5.

Put b = 5 into equation (i)

a + 2(0.5) = 3

a + 1 = 3

a = 2

Therefore, the price of soda is $2 per one and $0.5 for each popcorn.