how do i find childs dose? childs dose = y/? x adult dose

a childs dose of medicine may be calculated from an adult dose according to the following rule:

childs dose= y x adult dose

where y represents the age of the child in years. How many milligrams are to be given to an 8 year old when the adult does is 30 mg?

jess21390 said:

a childs dose of medicine may be calculated from an adult dose according to the following rule:

childs dose= yx adult dose

where y represents the age of the child in years. How many milligrams are to be given to an 8 year old when the adult does is 30 mg?

Click to expand...

What does the "x" stand for? What is the mathematical meaning of the underscoring of the "y"? How far have you gotten in plugging the given values into the given formula?

Please be complete. Thank you!

Eliz.

Re: how do i do this problem?

Sorry. The "x" is multiplication. The underscore under the y means division of something.

jess21390 said:

Sorry. The "x" is multiplication. The underscore under the y means division of something.

Click to expand...

Okay... but then: what is "y" being divided by? You have the child's dose, C; the adult's dose, A; and the child's age, y; with the equation apparently being:

. . . . .C = (yA)/(??)

...where the "??" is whatever is being divided into "y". Please confirm or correct.

Also, how far have you gotten in plugging the given values into the given equation? Please show all of your work and reasoning so far.

Thank you!

Eliz.

Re: how do i do this problem?

it doesnt say what "y" is being divided by. i guess i have to figure that out. i plugged in 8 for the age of the child and 30mg for the adult dose. Thats as far as i have gotten. the answer in my book says: y/y+12 x adult dose. so i plugged in 8 for "y" and 30mg for adult dose but i dont understand where they got 12.

Re: how do i do this problem?

jess21390,

You question cannot be answered without a little better notation. You must upgrade your math skills and be able to communicate. Sorry, but we cannot see into your head or onto the page of your book. Maybe you could scan a small image. Something must be changed as we clearly do not have any basis for a rational conversation. stapel is trying faithfully, but this is getting nowhere based on your original notation.

Re: how do i do this problem?

a childs dose of medicine may be calculated from an adult dose according to the following rule:

childs dose= y/? x adult dose

where y represents the age of the child in years. How many milligrams are to be given to an 8 year old when the adult does is 30 mg?

This is the question the book gave me. i typed it out exactly what is said in the book. The book gave me the answer to the question but i do not understand it. i even typed the answer for you. i dont know what else to say to make you understand the question because i dont even understand. i plugged in what i could.The book is saying that i have to divide "y" by "y+12" times the adult dose. but i dont understand where the 12 came from. That is as much information as i can give you. i dont have a scanner to have this scanned on the computer.

jess21390 said:

a childs dose of medicine may be calculated from an adult dose according to the following rule:

childs dose= y/? x adult dose, where y represents the age of the child in years. How many milligrams are to be given to an 8 year old when the adult does is 30 mg?

Click to expand...

You have two unknowns: the "childs[sic] dose" and the "?".

You have one equation.

As things currently stand, the exercise cannot be solved algebraically. More information (such as a second equation, or a value for one of the unknowns) is first required.

Eliz.

Re: how do i do this problem?

thank you.