Question

The cost for children under twelve at a certain buffet restaurant is a base charge of a dollar plus twenty-five cents for each year of the child's age. Represent this cost as an expression, using y to stand for the child's age in years. Then use the expression to find the cost for a child who is nine.

Answer 1

1+0.25y, 2.25

Explanation:

You would express the added 25 cents times the age of the child since the age is represented by the variable y, you would put 0.25y

then to find what the cost is for a nine year old you would multiply 9 by 25 and at the end of multiplying you would move the decimal from zero two times to the left. In case you don't understand how you could move the decimal from zero, there is always a decimal to the right of a whole number where the number ends its just not seen because there is no decimal in the number to represent. The decimal would still be there just it would be invisible but it becomes visible when there is a decimal number to represent.

hope this helps someone, keera

Answer 2

`Cost = 1 + 0.25y`

`Cost =3.25`

Explanation:

Given

`Base\ Amount = \$ 1`

`Additional = 25cents` of child's age

Solving (1):

Determine the cost function.

Represent the years as y.

So, we have:

`Additional = 25cents` * y

Convert 25 cents to dollars.

`25 cents = 25 * \$0.01`

`25 cents = \$0.25`

So, we have:

`Additional = \$0.25 * y`

The cost amount is then:

`Cost = Base\ Amount + Additional`

`Cost = 1 + 0.25y` --- This is the cost function

Solving (b): Cost of 9 years old.

In this case;

`y = 9`

Substitute 9 for y in
`Cost = 1 + 0.25y`

`Cost =1 + 0.25 * 9`

`Cost =1 + 2.25`

`Cost =3.25` --- This is the cost for a child of 9