Question

The price of 600 grams of candy and 1.5 kg of cookies was 4 dollars and 62 cents. What is the price of one kg of cookies if it is 1 dollar and 40 cents cheaper than 1 kg of candy?

Answer 1

The price of one kg of cookies is $1.8.

Explanation:

Given : The price of 600 grams of candy and 1.5 kg of cookies was 4 dollars and 62 cents.

To find : What is the price of one kg of cookies if it is 1 dollar and 40 cents cheaper than 1 kg of candy?

Solution :

Let x be the price of the kilogram of candy and

y be the price of kilogram of cookies.

The price of 600 grams of candy and 1.5 kg of cookies was 4 dollars and 62 cents.

600 grams = 0.6 kg

4 dollars and 62 cents = 4.62 dollars

The equation form is

`0.6x + 1.5y = 4.62` .....(1)

The price of one kg of cookies if it is 1 dollar and 40 cents cheaper than 1 kg of candy

So,
`y = x-1.40` ......(2)

Solving equation (1) and (2),

Substitute y from (2) into (1)

`0.6x + 1.5(x-1.40) = 4.62`

`0.6x + 1.5x-2.1 = 4.62`

`2.1x=6.722`

`x=(6.722)/(2.1)`

`x=3.2`

Substitute in (2),

`y = x-1.40`

`y = 3.2-1.40`

`y = 1.8`

Therefore, The price of one kg of candy is $3.2 and the price of one kg of cookies is $1.8.