I have a feeling I've seen this question before
anyway
A=number of hours that plan A is
B=number of hours that plan B is
so
on wednesday, 7hr
5A and 6B so
5A+6B=7
on thursday, 3 hours
3 of A and 2 of B
3A+2B=3
so we gots
5A+6B=7
3A+2B=3
elimination
eliminate B's
multiply 2nd equation by -3 and add to 1st equation
5A+6B=7
<u>-9A-6B=-9 +</u>
-4A+0B=-2
-4A=-2
divide both sides by -4
A=1/2
A=0.5
sub back
3A+2B=3
3(0.5)+2B=3
1.5+2B=3
minus 1.5 both sides
2B=1.5
divide by 2 both sides
B=0.75
plan A lasts 1/2 hour or 0.5 hour or 30 mins
plan B lasts 3/4 hour or 0.75 hour or 45 mins
Not sure if you can do this but it sounds like a velocity/time/distance equation.
d=vt
v=d/t
t=d/v
70 w/m = t
15 pages - 350 w/p
She can type 70 words per minute (w/m). There are 350 words per page (w/p). She needs 15 pages. So first you have to find how many words she can type in one hour. 60 minutes in an hour, she can type 70 w/p.
60x70=4,200 words per hour (w/h).
Next you should find out how many words on 15 pages total.
350x15= 5,250.
I would put 4,200/5,250 as a fraction to gage how much she has left. She has most of it done already in ONE HOUR. Reduced, she has done 4/5s of the essay. Now you just need to get 1/5 of 5250, which is 1050.
She needs to do 1050 words. If one minute is 70, do 1050/70 which is 15.
The answer is 1 hour and 15 minutes.
I think... ;)
The choice isB
all the numbers in that choice decrease in numerical order
1.x+16
2.x-8
3.12/x
these are the algebraic expressions
