I just put 225 in the whole thing and it worked out to get the probability they showed, my friend put both in when u find the z values, and said you get negative z for 342.25 i think? you didn't really have to say why you picked what?
Yeah I subbed back in and you do get -Z, somehow didn't think to take the other root :/ hoping I get 6/8 or so for method marks
I just put 225 in the whole thing and it worked out to get the probability they showed, my friend put both in when u find the z values, and said you get negative z for 342.25 i think? you didn't really have to say why you picked what?
Basically 342.25 would have worked if you took the negative square root at the bottom but idk
I think and hope it's 225 cause that worked flawlessly when i plugged it back in and it only asked for 1 value
Hey guys for the 8 mark question i got n=62 which i know is wrong, but i want to know how much marks you think i could get, because i made a mistake when squarerooting 0.16n so i didnt do the quadratic equation
How did people get 225? I ended up solving the quadratic p^2 + 0.7p - 55.5 <0 something like that 🙈
You get 555-2p=7sqrtp and if you square all of that then you got 4p^2 -2269p + 555^2 =0 and then if you solve it using the quadratic function you get two answers 225 and something else with a point 25 in and as you were finding n it had to be a whole number so 225 was the answer
Hey guys for the 8 mark question i got n=62 which i know is wrong, but i want to know how much marks you think i could get, because i made a mistake when squarerooting 0.16n so i didnt do the quadratic equation
I would say 4, an M1 for using normal approx, an A1 for half cc, and an M1 and A1 for getting to 55.5-0.2n = 1.75*sqrt(0.16n)
I just put 225 in the whole thing and it worked out to get the probability they showed, my friend put both in when u find the z values, and said you get negative z for 342.25 i think? you didn't really have to say why you picked what?
You get 555-2p=7sqrtp and if you square all of that then you got 4p^2 -2269p + 555^2 =0 and then if you solve it using the quadratic function you get two answers 225 and something else with a point 25 in and as you were finding n it had to be a whole number so 225 was the answer
Ah thank you, sorry, but how was the 2n derived? As I thought 1.75 (z value) = (55.5 - n) / (0.16n)^0.5