How to do Upper and Lower Bounds A/A* GCSE Higher Maths Worked Exam qu revision, practice & help

Practice GCSE exam questions on Upper and Lower Boundaries. These are all A/A* Questions. These questions are often poorly done on exams as students usually fail to realise what the question is asking.
links to Questions

[murtadha]

Thank you very much, finally a teacher in a youtube video that goes at the actual hard question that really come up in the exam. Much appreciated.

[RawMaths]

Thank you for your comment Mary-Kate. In most of my videos there is a symbol in the top right corner denoting a calculator for calculator based questions and a calculator crossed out for none calculator based questions. So as you can see these are calculator based questions.

[diyajain]

In the 3rd one the radius is rounded to nearest mm
So shouldn't we convert 6.2 cm into mm first?

[ItsMegaMeggy]

these are so useful! thank you! just one question, at 7:52, why is the answer for lower bound 35.6 35.5 and not 35.55?

[willbennett-lynch]

Very helpful! Helped me get the last question on this paper.

[mominahussain]

In the last question is it possible that you give the answer of m as 0.23 as it would be the same for the max and min values

[mary-katewildsmith]

Would this be on calculator or non calculator

[izzyr]

Very clear - got all that - Thank you very much.

[FAITHXHOPE]

Are there any kind keyy things you need to know when doing Upper and Lower bounds?

[mjbadboy]

I don't understand the significant places like for example 27.6 to 3 s.f and 23.4 to 1 s.f. I don't understand them

[Novokuv]

When you're working out for upper bounds results, why do you divide by a lower bound and not two upper bounds? I am thinking to yield a bigger result using a smaller number when dividing?


Also, how do you know when to use a upper and a lower bound when doing the formula since the question didn't say at all apart from calculate the lower bound.

[jamiemcintosh]

obviously the maths is the same but are these lessons viable for gcse 2019 with the new spec

[bethelfrimpong]

there is a mistake on the 3rd question, you need to convert the 6.2cm to mm before you can work the upper and lower bound. Sorry for interruption

[Arya-sxnz]

hi
i put the right values for the second question but my answer was different to yours
my answer was 5.10 to 2 d.p