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Mrs Tibble’s / Mr Atkins’ Year 9728 comments to Mrs Tibble’s / Mr Atkins’ Year 9 |
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okay thanks! (i didn’t know i was on yr9 page sorry)
So which year are you? The GCSE link might not be suitable lol
Hello Mrs Tibble
Just saying Hey. How are you? Haha.
Hello Mrs Tibble
GUESS WHAT
i did all my homework 
but i’m leaving question 38 till like saturday because my brain was about to go ‘kaboom’
Hey Mrs Tibble
Did you like my messed up playing in celebrating success? Oh and i’ve done q37 but i’m not so sure about 38, i think i know what i’m doing but i might get pat to help me maybe
Mrs Tibble! question 38 is all in jibberish! i dont get it
Help
Hi Emily,
Think about what we have just learnt about rounded values. For the first piece of wood you are told its rounded measurement so you can work out the smallest its true size could be and the biggest its true size could be. OK so far?
Now do the same with the second piece of wood.
If the two pieces both had their biggest possible values, what would be left over?
If the two pieces both had their smallest value, what would be left over?
These 2 answers are what you need.
Hope that helps
Now you know why I gave it 3stars!!
Good luck,
JT
i’m really stuck on q38, well not really stuck but quite stuck, and i read what you said to emily but i don’t get what the biggest possible value and the smallest possible value are?
Helppp!!
Hi Alice,
I haven’t got the text book here so I can’t remember the exact numbers but here’s an example.
Suppose the first piece of wood was 1.5m correct to 1 dp. That means its true value could be anywhere from 1.45m (smallest value possible which rounds to 1.5) up to 1.54m (largest value which would round to 1.5 as 1.55 would round to 1.6)
If you imagine drawing it on a number line its the start and finish values.
Does that help?
JT
oh yeah i did that so the smallest and biggest values are actually on the number line?
Hi Alice,
They would be if you drew it. You don’t need to draw it, just work them out and use them for the last bit of the question.
Have fun
JT
MRS TIBBLE! q38 is confuzzling me. I read all that you said to alice and emily but i still don’t understand the biggest and lowest value…help please
Hi India,
If the two pieces of wood are the longest they could be (and still round to whatever the value is) then when you add them together you’ll get the biggest amount of wood which could have been cut off. Take this away from the full length and that will tell you the size of the smallest leftover piece.
Do the same with the pieces as small as they could possibly be and that will give you the size of the biggest leftover piece.
JT
My brain is not working today. What is the number in the middle? Like the one that everything is rounded to? 450mm?
my sister just explained it to me..but i still really don’t understand any of it.
India, I don’t have the book here so I can’t tell you the exact numbers.
What size is the first piece and what is it rounded to?
well the wooden pole is 450mm and the piece cut from it is 200mm to the nearest mm. (:
OK. So if the cut piece is 200mm to the nearest mm, that means it’s closest to 200 rather than 199 or 201. OK so far?
For this to happen, it could actually be as small as 199.5 (cos that would be rounded up to 200)
or it could be as big as 200.4 (200.5 would round up to 201). I’m just using one dp here otherwise it gets a bit silly for a piece of wood!
Therefore its true size could be anything from 199.5 (smallest value) to 200.4 (biggest value)
Does that help?
Do the same with the 2nd piece of wood, then work out the size of the leftover piece.
I UNDERSTAND!
My sister was talking rubbish. Haha thankyou 
Then sort out your sister lol!!!
Oh and is the second piece of wood 250mm?
No. Aren’t you cutting off 2 lengths from the same big starting piece? Or am I not remembering the question properly?
the question is – A wooden pole is 450mm long and a 200mm length is cut from it. Both of this measurements are correct to the nearest millimetre. What can you say about the length of the remaining section of the pole?
I don’t know if it’s 250mm or not.
Oh I see. The 450mm has been rounded too so the true length of the pole could be anything from 449.5 to 450.4. Anything in this range would have been rounded to 450.
You need to work with these lower and upper values along with the lower and upper values of the cut piece to see what is left over.
ie what if the start piece was at its smallest and the cut piece was at its biggest? How much would be left over?
Then do it the other way round.
Do what you can then stop: you’ve spent enough of your saturday on this!
thankyou. i think i may stop here. I have a lot of homework to do
Thankyou so much for your help (:
Hello Mrs Tibble
I’ve done all of page 36,
but I have got really stuck on question 35
help!
Hi Jasmine,
I don’t have a book here so you’ll need to tell me what the question is about? Is it the box of tiles one which we looked at in class?
Hello Mrs Tibble
hi
Hello Mrs Tibble just singing in
Esme
Aaaah Mrs Tibble help! What’s 0.125 as a fraction in simplest form? I know it’s 1/8, but i don’t know the thought process behind that :S help please
Hi Alice,
As it’s 3 decimal columns, you have reached the thousandths so it’s 125/1000 then you need to simplify it.
JT
Mrs tibbel!
Hello there
Welll… you see on question 10 of the homework, i know why its correct but im not sure how to explain it!
Hi mrs tibble
i am stuck on questions 10 and 11. Please help me thankyou
Hi Emily, just try to put it into words!
Hi Rachel,
Try using some real numbers to try out the statements and see if you can work out what is going on.
hello
um how do you set out the homework? can we set it out like the questions we did in the lesson?
Yes Alice, that will be fine.
oh okay thankyou
for the homework, could you do it like this? – gain = 5%
new salary = £32000 x 5
= £160000
oh and is that right as well?
Lol Alice! You wish
Unfortunately pay rises don’t quite happen like this 
5% is 5/100
5% rise means new % is 105% so multiplier is 1.05
Do 32,000 x 1.05 to get the new salary, or 32,000 x 0.05 to find just the increase.
JT
MRS TIBBLE!!
You know the homework..q1? Well for the 10 years interest do we have to do ten years? or just times it by 10?
INDIA!
Since they are all the same in simple interest you can do it 10 times and add, or do it once and multiply. I know which I’d choose
So if you multiply do you work out the interest and times that by 10?
India,
Yes because it’s the same each year for ten years.
Mrs Tibble, you know for the percentages test on tuesday, which topics are we meant to be revising? Like percentage increases & decreases, bank interest, finding a percentage of a quantity etc? Oh and also are we allowed a calculator in the test?
Thank you
Hi Alice,
yes, everything we’ve done in this section including the decimals and fractions which are equivalent to the percentage.
Yes to calculators apart from the topic i just mentioned.
JT
ohh okay thank you