Question

Mixing two kinds of candy the price of which was $2 and $4 per pound, Ella got a 10-lb mix of candy, which cost $2.90 per pound. How many pounds of each candy were used for the mix?

Answer 1

4.5 pounds of candy y

5.5 pounds of candy x

Explanation:

Given

Let x and y represent the two candies

`x + y = 10` --- the sum of both candies

`2x + 4y =29` ---- the worth of candies

Required

The pound of each

`x + y = 10`

Make x the subject

`x = 10 - y`

Substitute
`x = 10 - y` in
`2x + 4y =29`

`2(10 - y) + 4y = 29`

Open bracket

`20 - 2y + 4y = 29`

`20 + 2y = 29`

Collect like terms

`2y = 29 - 20`

`2y = 9`

Solve for y

`y = 9/2`

`y = 4.5`

Recall that:
`x = 10 - y`

`x = 10 - 4.5`

`x = 5.5`