hello and welcome today we're going to be looking at bid Mass which is the order of operations not to be confused with christmass which is the order in which we open presents so hopefully by the end of this session you'll be quite confident in how to complete bid MK calculations so that you can then move on to working with formulas I'll leave a link at the end of the video for the next topic which will be formulas but let's dive in with bid mass by operations we mean addition subtraction multiplication and division as well as brackets and squares of numbers and you've got to be really careful with this so if you see 20 + 10 * 2 and you do that in your head you may get the answer of 60 which unfortunately is incorrect and that's because it's not using the order of operations if you've got a smartphone you use the calculator and you do 20 + 10 * 2 you'll get an answer of 40 which is indeed correct and that's purely because your calculator on your smartphone is following bidm so what does bid Mass actually stand for B is brackets so when we're doing a calculation if you see any brackets that's the first thing you've got to be working out so whatever is in your brackets and following on from the brackets we've got the indices which in functional scales is squared numbers or powers of so it's not necessarily squared it could be to the power of four power of three which it we refer to as cubed or the power of two there for example which is squared we do also see in there the square root of something we're not looking at the square root we're just looking at the one on the right hand side there which is squared units uh We've then got Division and multiplication followed by addition and then finally subtraction so this is the order in which you should do your calculations now Division and multiplication are grouped together so just to kind of break the the rule in a little bit you can do those in whichever order they appear in your calculation however if you're unsure just follow the the proper acronym but that also applies to addition and subtraction you can do those in whichever order they appear in the question uh as well as long as your addition and subtraction is done after any Division and multiplication you should be absolutely fine but always do your brackets and your indices first so let's have a look at this question here we've got 5 + and then in bracket 6 * 2^ 2 + 7 so what we're going to be doing here if we're following bid mass is the two squ first so when we're looking at a power of something so indices uh if it's squared it means we're just timesing it by itself so when you're doing areas and you've got pi r squ if something is squared you're timesing it by itself so to the power of two so here 2^ 2 if it was to the power of three you'd do that again if it's to the power of four you'd multiply it again it's to to the power of five You' do it again and so on and so on so where where I'm saying the power of five that would be if that little two that's floating in the air would be a five then it would look like that but it's not we're doing we're doing squared so um we're just doing 2 * 2 so 2 * 2 is four So within that calculation we could actually rewrite that and replace the 2^ squ with the number four I'm just going to put that there let's get rid of the 2^ squ so we've done that bit so the next bit within our brackets is uh the multiplication if we're following bidmas so it would be 6 * 4 so 6 4 is are 24 and then we're going to plus 7 so 24 + 7 is 31 so the value of those brackets is 31 so all we've got left is to plus the five as our final part so the answer to that question is 36 so as you can see we did the indices F uh went to the brackets first first thing within the brackets was the indices which came out as four uh then we did 6 * 4 plus the seven gave us 31 so the value of those brackets was 31 and then we just added five and that gives us the answer of 36 so as long as you're following these orders of operations so brackets indices Division and multiplication and then addition and subtraction you can't go wrong we got some practice questions we're going to go through do feel free to pause uh these as we go and have a go at them yourself but um this first particular question I'll kind of run through just to give you another sort of uh demonstration but we've got 3 + 16 * 2 so remember if we're following bid Mass uh here we've got an addition and a multiplication remember we do the multiplication first if we're looking at bid Mass so 16 * 2 is 32 2 so that calculation there the next one we're doing is the addition so it's 3 + 32 and that gives us our answer of 35 following on from that we have 16 * 2 + 3 so 16 * 2 + 3 first thing we need to do is the brackets so the 2 plus the three is five so then that calculation becomes 16 * 5 and that gives you 80 as an answer so just to clarify the reason why we did the plus first is because the Plus in is within the brackets Plus in that's the technical term the addition the addition um so yeah it's because your addition is within the brackets so brackets is the first thing you do whatever is in your brackets you calculate first following bid mass and then it's the final bit there which was that multiplication okay have a go at this one on your own do feel free to pause and then I'll go through the answer okay so we've got 3 * 2 + 8 ided 4 so we're going to be following bid mass now remember I said that you can do your multiplications and divisions in whichever order they appear in your calculation so we can do 3 * 2 is 6 8 / 4 is 2 add those together and you've got an answer of eight so well done if you got that one right and then the final question we've got here is 3 + 42 ided 7 have a go at this one okay so uh looking at the working out of this one we're going to be doing the division first so 42 / by 7 is 6 and then finally 3 + 6 is 9 so if you got nine as an answer for that question huge well done now we're going to have a look at these next ones true or false so do feel free to work these ones out and we'll decide whether these ones are true or false so have a go to this question pause the video is the answer six okay if you said true well done we're looking at 12 / 4 is 3 and then 3 + 3 is 6 so that one is true absolutely have a go at this next one 12 / 3 + 3 = two true or false that one's false absolutely seven so 12 / 3 is 4 4 + 3 is 7 okay now we've got one more to do and maybe it's a little bit trickier than the other ones cuz we do have an indices in there so 4 + 2 * 4^ 2 is 96 true or false okay that one is false as well so the answer to that one should be 36 so 4 * 4 for 4 squar uh so we're looking at the indices first four fours are 16 uh then we're going to do multiplication so 2 * 16 is 32 and then finally the addition at the start of the calculation there which is 4 plus so 4 + 32 is 36 okay so hopefully feeling a bit more comfortable and confident with your understanding of bid mass and Orders of operations so you should be able to apply this uh method to any formulas that you might come up against uh which could be formulas for area so if you're working out the area of rectangles and circles it could be used for volume so for example the volume of a triangular prism it could even be for this extremely scary formula which is the surface area of a cylinder compound measures and finally Pythagoras Theorem which everybody hated at school but you'll be thankful to know that we don't do this in functional skills but that's it for this video uh do click on the video that's on screen now which will be the formulas and that will teach you how to apply bid Mass to formulas cheers I'll see you in the next one