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Mr Brewin’s Year 9243 comments to Mr Brewin’s Year 9 |
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Have you done your handwriting homework mr b? Which letter did you get up to – you get a gold stamp if you get up to letter c! lol
Anyway as proffeseurs Prof Quist and i shall not have time to go to your detentions as we will be to busy studying what that guy spent most his life doing (the guy we watched a video on)!
The only problem is that on this blog you cant see mr bs sarcastic smirk so i dont know when he is puling our legs!
Yes, i’m sorry our detentions will not be possible. we will be studying too hard. yes i remember that video. No Mr brewin has to get up do ‘d’ to get a stamp Nina, we can’t just give them out for ‘c’s it has to be a ‘d’ at least
that could be a problem Prof Pimblett
hmmm detention sounds fun!!!
Fair point, and for every 5 stars, he gets to get a new doll for his doll collection!
Hes going to be working extra hard this term – no more studying the footie! 
Mr Brewin, Professors Quist and Pimblett want your handwriting in during registration first thing tomorrow to mark it otherwise you might be in detention for life!!!
(have you worked out that i am not a robot yet so can you take away that code thing… its rather annoying, Prof Pimblett i think we need to work out how to get rid of it)
hmmmmmm… maybe the formula pi(which i dont have the button for) r2…
I have no colored paper for my history so i will get it tommorrow, Prof Quist you are not to let me forget! Also (Almost certainly going to be Prof) Treece still hasnt sent me the biology results so i will capture her tommorrow as tehn it wont be her birthday, and she wont have cake! 
YEAH IM NOT A ROBOT – M B IS THE ARTIFICIAL ONE!
I think they should just re name this site ‘Prof Pimblett and Prof Quist’ blog!
can someone help for both question 11 and 14 on pg 106
i dont get how ur supossed to add and take away at the same time
Hi Azaly,
Is this Q11 at the top of the page or near the bottom?
Method the same for both. Multiply all the pairs together looking at the signs of the 2 things you are multiplying. Answer is + when signs are the same, – when they are different. Then collect them all together and simplify – if you can (it’s not always possible)
JT
thank you very much
it help a lot
by the way it was the q at the top
i really need help with the q 9 to 11 on pg 153 i just dont get it ive tried and tried and it does not work
I don’t know how you do questions 1-3 on p153 ex7I… do you do 2.5 cubed and then at 0.5 or are you meant to do something else… ?
this what i did
2.5(2.5+0.5)=
2.5×3=7.5
thats the answer
That’s right for Qu1 – 3 Azaly – well done!
For 9 onwards:
55^2 – 45^2 = (55 + 45)(55 – 45)
(Difference of 2 squares factorisation)
= 100 x 10 = 1000
Look carefully at the example in the green box above it…
Thanks Azaly
yer i did but i forgot where the 2 came from
thank you i get it
what do you do about the 0.5?? I’m confused again!
I dont understand question 1? It its 2.5(2.5 + 0.5 )
dont you do 2.5 x 2. then 2.5 x 0.5? i cant make it fit 7.5??
In Qu 1 you are factorising the 2.5^2 + 0.5×2.5
2.5 is the common factor, so it becomes: 2.5( 2.5 + 0.5 )
Because 2.5 + 0.5 = 3, the whole question is then 2.5 x 3 = 7.5
Thaank you, i get it now
Thanks but how do you work out the common factor for number 2? do i need to do that tree thing?
i get question 1 but on q2 is it 3.7(3.7+3.7) but then i dont understand the rest
Kate and Pia,
In Q2
1.3×3.7 + 3.7×3.7
the term they have in common is 3.7 so that goes outside the bracket, and what’s left goes inside the bracket:
3.7 ( 1.3 + 3.7)
Bracket adds to 5 so sum becomes 3.7 x 5
why does one of the common factors always seem to dissappear? e.g. Q2 1.3×3.7+3.7×3.7 –> 3.7 (1.3+3.7) = where does the third 3.7 go?
Nina, it doesn’t disappear – writing it OUTside the bracket means that it applies to both terms INside the bracket. The bracket format is therefore a type of shorthand. If you multiply out the bracket to get rid of it, the 3.7 will appear again MAGIC
WOW… magic!
thanks
lol!
do you know whether mr b will be at these maths class things on saturdays or is it just pupils?
Not sure what exactly you are referring to – is it the maths masterclasses? They are run by outside people, not us.
yeah i mean those, if mr b isnt going, i might consider… otherwise i would spend my saturday being a target for flying books and generally being proved wrong ( i probably still will be!
) 
Hehe! Go for it Nina! You’ll be safe, I’m sure
The people I know who have been have always enjoyed them.
i really need help for q’s 10,11,12
i just dont get
please help
Hi,
I was wondering if anyone would be able to help me; if you know the volume and the diameter of the base of a cylinder, how do you work out it’s height?
Thanks in advance for any advice
Hi Olivia,
Volume = area of cross-section x height, so
Volume/area = height
Area you can work out as it’s a circle so pi x r-squared (r is half the diameter)
Plug all the numbers in and you’ll have the height.
Check your answer by working the formula forwards to see if you get the right volume (it won’t be exact because of rounding errors when you use pi)
Have fun
JT
I am slightly stuck on the homework mr brewin set us it’s p284 q9 and i am not quite sure how to go about this, thanks
Hi Pia,
Can you think it through in words first, before you worry about what to do with the numbers?
JT
I am very stuck on page 284 question 6 – the paint one.
i am not sure how to do it
Hi Emily,
Apologies for the delay – Cipher Challenge took over!
Picture zooming in on the layer of paint: what 3D shape will it be? How do you work out the volume of that shape? You don’t know all the measurements – one of them is what you have to find – but you are told the volume is 1 litre (1000 cm cubed) so you can work your volume formula backwards to find the missing measurement.
Good luck.
I’m still stuck on q9 on p284 because i don’t know how to find out the volume of the jug with only the diameter? do i need to find out the area or something else entirely?? Thanks
Hi Pia,
You don’t need to know the volume of the jug; you just know it’s big enough to take the water you pour into it.
You can work out how much water you pour in (volume) because you are given the measurements of the tumbler. No water spills so that must be the volume of water in the jug.
Water in jug takes the shape of the jug (cos that’s what liquids do!) so it forms one big cylinder of known volume.
Vol = area of cross-section x height.
Area = pi x r-squared
so the only unknown is the height.
OK?
thanks
can some1 help me with q’s 20-22 i think i know what to do much im just not sure.
do u have to work out the percentage then add it on to the orginal weekly pay.
thanxz azaly
Ok, for Qu 20 for example, 12% on weekly pay of £100 would give you £12 pay rise. Then do 8% of weekly pay of £250 and see if that’s bigger… then say which is better pay rise, and by how much.
hi can someone help me with q 11 on pg 71 i really dont understand
thankx
Hi Azaly,
Think about the problem in words first, without worrying about the numbers.
The man’s wage is in 2 parts: he gets a basic wage of £245 a month whether he sells anything or not. Anything on top of that is commission – a sort of thank you for selling stuff! Start by separating his money into the bit he always gets and the part which is commission. You are told that the commission is 2% of the value of the sales, so you can scale that up to 100% to find out what the sales were.
Does that help?
JT
i am really stuck on question 10 b, p71. I think I understand what the question is trying to ask, but I don’t understand how to work it out. can somebody help me please???
Hi Sophie,
You need 2 values: the value after one year, and the depreciation ie how much value it lost in that year. Write these as a fraction first of all, with actual value on top. Simplify the fraction then turn it into a percentage.
Any use?
JT
i think so therefore i have to
take away 245 from 955 = 710 (commisions)
i get it up to there and i understand what you are saying but what then? do i find 98%
so 710 x 0.98
or am i going the wrong way
Ok, I understand it now. Thank you