plz help
Jack's pet dog has been prescribed 40 mg of a medicine per day. Each pill of the medicine has 12 mg of the medicine. Jack has to give his dog a total of 20 pills. If Jack gave his dog medicine for x days, use the expression below to interpret the situation.

12 • 20 − 40x

Part A: What does 240 represent?

Part B: What does the second term represent?

Part C: What does the entire expression represent?

Question

plz help
Jack's pet dog has been prescribed 40 mg of a medicine per day. Each pill of the medicine has 12 mg of the medicine. Jack has to give his dog a total of 20 pills. If Jack gave his dog medicine for x days, use the expression below to interpret the situation.

12 • 20 − 40x

Part A: What does 240 represent?

Part B: What does the second term represent?

Part C: What does the entire expression represent?

phi · Answer

Each pill  has 12 mg of the medicine
total of 20 pills

20 mg per pill times 20 pills  is 240 mg (of medicine)

phi · Answer

can you answer
Part A: What does 240 represent?

anonymous · Answer

240 represents 240 mg. right?

phi · Answer

yes.  but there is one more idea...  the total amount of medicine is 240 mg
(divided into 20 pills)

phi · Answer

40 mg of a medicine per day
for x days

what is 40x  (40 mg times x days) ?
in other words,  what does 40x represent ?

anonymous · Answer

40mg in x amount of days ?

phi · Answer

40 mg times 1 day = 40 mg
40 mg times 2 days = 80 mg
40 mg times 3 days = 120 mg

what are we keeping track of here ?

anonymous · Answer

How much medicine is being taken by each day

phi · Answer

how about,  how much medicine we used up ?

anonymous · Answer

that to also works!

phi · Answer

What does the entire expression represent?

12 • 20 − 40x

the first part 12*20 = 240  is how much we start with
40x  is how much we used up (after x days)

what are we figuring out here ?

anonymous · Answer

How many days we would have medicine until we ran out

phi · Answer

it can't be days.
look at the equation

240 mg  -  40 mg/day * x days

remember that 40x means
40 mg times 1 day = 40 mg
40 mg times 2 days = 80 mg
40 mg times 3 days = 120 mg

how much medicine used up. it is so many mg

if you start with 
240 mg  and subtract  40 mg (for example)  the answer will be in mg
not days.

try again.  what are we figuring out?

phi · Answer

you could look at what you get for x=1, 2, 3

240 - 40*1 = 200
240 - 40*2=  160
240 - 40*3= 120

what are we calculating...

anonymous · Answer

240mg - 40 a day. = 200
We are calculating how much mg we take each day.

phi · Answer

we know we take 40 mg each day

anonymous · Answer

how much mg is left?

phi · Answer

yes, How much medicine in mg we have left after x days

For example, after 3 days, we have  120 mg left
(we use the formula  240 - 40*3 = 240-120= 120 mg left)

anonymous · Answer

You the best Phi ! lol

phi · Answer

yw