The answer is the first option
y=3/2x+5
No they are not equivalent
There are 5 letters in the word "prime"
Imagine we had 5 slots to fill. They are empty initially.
Slot 1 has 5 choices to pick from
Once we pick a letter, we have 4 choices left over for slot 2
Slot 3 will have 3 choices
Slot 4 will have 2 choices
Slot 5 will have 1 choice
We have this countdown: 5,4,3,2,1
which multiplies out to 5*4*3*2*1 = 120
There are 120 unique ways to arrange the letters. Order matters. Because order matters, this is a permutation.
I would personally take the number three and trow it out the window but that's not what we are talking about
1) in one minute for first wiil be 1/20
the other 1/30, it means that A paint in one minute 1/20 and B 1/30 then A+B in one minute 1/20 + 1/30 = 3+2/60 = 5 / 60, 5/60 = 1/12
if in one min they make 1/12 then in 12 min they paint all the wall