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Math Bootcamp

Added Sep 29, 2020 •

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Math Bootcamp 9/29/20: Fractions - Multiplying / Dividing

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are the two of us who got some answers in there so I'm going to go ahead and start working out number 9 out I'm going to go ahead and write it up here we have a little more space so we have 5 / 8 3 1/4 the first thing we need to do is as in the other problems is go ahead and convert this mixed fraction into an improper fraction and we do that by multiplying the denominator times a whole number and then add that to our numerator so we're going to have 5 or 8 times that we have four times three which is going to be 12 and then I add 12 to my numerator which is one of the total of 13 / 4 I can go ahead and get some Once Upon a cross on the bottom of when they have 32 on top when I go to my calculator and I'm going to have five 13 5 * 1565 and we have 65 / 32 sure as an improper fraction I can go in now I can go in and converted to a mixed number I'm going to go 65 and. read 32 so how many times does 65 go into 32 it gives me 64 - 1 and like I said in the previous problems you start at the top that's your phone number you go down below that's your numerator and you keep going to the right that's your denominator I'm going to go ahead and write my answer again 2 + 132 going to recess now we're getting into division how exciting so that was multiplication I was not so far yeah so just this to do with a recap into the multiplication when you have problems like number one you just multiply straight across oops I caught that wrote a division sign here that's what she wants break when we have problems like number one we just multiply straight across meaning the numerator X in numerator and the denominator times it's not meter let me have problems like number two convert the highlighted part which is the mixed number into an improper fraction before we multiply when we have problems like number three where they originally just give us. Which is a fraction times a whole we simply place it over one make it a fraction and then we just multiply across like we would in problem number one number seven is only problem when you have two mixed numbers are to mixed fractions you convert them both into improper fractions multiply across and then convert back into a mixed number for your final answer different variations that you could see for multiplication problems now we're going to go into Division and I'll explain it to separate ways and you guys let me know which one is an easier way of understanding it so we have 7/8 divided by 1/16 option number one to solve is Houston do the lifts you flip your second fraction making it 16/1 and you change this to multiplication and you saw if you have eat at the bottom 7 * 16 is 112 option number one right without me taking it into a mixed fraction that  number one number two is when you have it raining like this what you do is exactly you multiply in a zigzag formation so we could go 7 * 16 is 112 Google * 1 is ate some I'm zigzagging and you know what let me even change the color of the second so it's a little more clear that makes it a little more so those are your two options which one seems like it would be easier to memorize or using practice the first one of the second the second one yeah so so I'll go see what they say I'm going to stick with the second one for the session but just know that you have either option either you flip your second fraction and multiply across or you do this zig zag multiplication where you go from the top top bottom top bottom so I keep those up there thank you I'm actually recording this section two so I'm going to go ahead and post it up I'll later on so you guys can also review this I'm going to go back to report who recorded his friend I was doing informal for a bit and doing his unrecorded since it was smaller classes but I think in the long run better off to just have it all recorded hahaha died over next time so we have one 12 / 8 4 as a mixed number so it goes into 11 one time 3 B12 and those in four times so or a flat 14 okay and then we have option one Berry lip the second equation in X cross and then we have option to so let's all option one first so when we flip the second fraction of an X across we have four x 9 which is going to give me 36 and then I have 5 x 4 which is going to give me if you use a second method we do the zig zag so we go 4 * 9 equals 36 5 * 4 equals 20 and so we get the same answer I want to go and write that down here 36 / 20 now I'm going to go ahead and erase this and so how many times does 20 go into 36 yeah it's only going to go in at one time subtract time and I have 16 is my reminder I start off with this is my phone number I work my way down to see my numerator and this and I do not make me I have 1 and 16 over 20 an hour I can still reduce my fraction right so I need to think about in my head what's the largest number that I can think of that can divide evenly into both 16 and 20 yes so 16 / 4 is going to give me for and how about 20 / 4 what does active mean perfect so I can go down here right or 1 + 4/5 yes if you divide 4 by 5 you're going to get .8 as if you go 4 / 5 unit 2.8 and then you can have that too your whole number which would be the one send Anon the calculator to you can also I mean depending on which calculator you have what type of capillary have you can also type it in fraction depending I don't know with the fuse in your phone or if using Max will talk later but on some on the computer on some you can you can have it solved as a as a fraction okay so what am I going to do here I have a whole number divided by a fraction remember what we do when we have the whole number and I can go ahead and solve this one you can buy zig-zag cycle 12 * 4 equals 48 can I go 1 * 1 equals what and remember anything 48/1 is it going to be 48 that's man's okay just like the last one we did what it what do I do to the 6th 4/1 / 1 and then the 2 and 1/2 I need to go ahead and convert that into an improper fraction so I have 2 and 1/2 I multiply the two times at 2 and then I added to 1 32 * 2 is 4 + 1 is 5 75 / 2 so I have 6 / 1 divided by 5 and I can use the zig zag method right I can go six times 2 equals 12 1 * 5 equals 5 Necromancer right here 12/5 floor how many times does 5 go into 12 2 * right when is time you can meet you so start of talk and then I go to my right hand side this is my new this is my phone number this is my numerator and then 5 is not denominator for 2 and 2/5 nature so what let's take care of 1442 conversions to do let's get right into it I have 3 3/4 which is going to become 4 * 3 is 12 what's 3 is 15 * 15 or 4 and then I have one and 2/3 so I go 3 * 1 that's 3 + 2 that's five * 15/4 / 5 / 3 and I can use that zig zag message 15 * 3 equals 45 and 4 * 5 equals 20 or how many times does 20 go into 45 2 * 6 and so then I 40 and have a remainder of 5 so I start up top here this is my whole number this is my numerator this is my do not me oh and question can I simplify 5 over 20 is there a number that can go both into 5 and 25 thank you so 5 / 5 is going to be the one and 20 / 5 is going to be for 4 full moon all right this one is simple and easy we just play * 9/1 so we have two fractions multiplying each other or dividing each other I'm sorry enemigo 9 * 3 equals 27 1 * 1 equals 1/1 is going to be itself right so my answer is just going to be okay what do these last three up here so I have 26 2/3 I go 3 * 26 and then add that to 2 I don't know what that is off top my head so I go to my calculator 7878 + 2/3 and then I have 3 and 1/3 so I go 30 * 3 is 9 + 1 is 10 80 * 3 240 and then I go 3 * 10 3 + 30 Ruidoso vacation yes you can say what you said so because we have the two zeros right here you can go ahead and cancel and then now we just have to 24/3 so 24 / 3 is going to give us our zero I mean our 8 I'm sorry anytime you have same number of zeros on your numerator as you doing the denominator you can just cancel those observations you can all right two more and then we can get into the sun word problems search sweetheart of 40 and 3/8 weego 8 * 4 + 3 suicides at 3:20 what's 40 set 320 + 3 * 323 / 8 and then we have 4 1/4 x 4 x 4 which is going to be 16 + 1 17 2 Chainz Samsung big numbers here what's 323 * 4 1290 2200 8 * 17 136 okay wow for some reason with the numbers got big I got a little uncomfortable and so now it's let's go ahead and divide this out I 136 when I resolve this we have a room somewhere to go to my calculator and see how many times 136 goes in and goes in 9 and 1/2 x so Title Nine 36 magazine 1224 magazine 68 and so have 9 and 68 / 136 and surprise surprise if we think about what's the largest number that can go both into 68 and 136 it's actually 68 so we can have divided by 68 and we're going to get 9 and 1/2 another reason I try that was because when we did it into a calculator or when I did into calculator I got a 9.5 so I knew that point 5 as a decimal would be written as 1/2 as a fraction I gave me the clue. Okay maybe this fraction is divisible by 68 but otherwise if I didn't know that I would just keep dividing by 2 by 2 by 2 until I end up add 1/2 and I can't go any further okay and then finally ending off it's a nice small reasonable numbers we have 3 and 7/8 pellet smoker accessories so I want to go 8 * 3 for 7 singing can you give me 31 / 8 and then I have 5 and 1/6 it's going to be 6 x 5 which is going to give me 30 + 1 is going to be 31 31 hours today and I'm going to go ahead and use my zig zag method 31 * 6 is a 186 and 8 * 31 248 so now we can go ahead and reduce this let's try to what's fire let's try dividing by two right Seneca Kansas 2 / 2 / 2 * 186 Dubai to Disney 93 248 / 3 days me 124 all right so done with that we just want multiplying and dividing fractions so is a lot of work but we're finally done now we can get into the word problems see what's going on here so $0.19 a city is considering raising taxes to build a football stadium a survey of registered voters yielded the following results against tax hike 716 for tax hike 16 and undecided 3/8 answer the question is if 400 people were surveyed how many support the tax hike so first you have to determine what frac support the tax hike 3/16 are supporting the tax hike is the total of 400 people so we have 400 people and 3/16 of them supported it so what do I need to do in order to multiply it out first stop the Gyros 92 places / 1 I think it over one so that if the fraction and I can just multiply straight across so up top of Anna have 1200 + at the bottom when you have 16 and now all I need to do is divide my top by my bottom consignment all right we're going to have 75 is there answer is that make sense we did I asked you how did you get the the 3/16 how did you know because I got that right here and that's because they want to know what is that that I needed to xiamen because it was asking us how many support the tax hike so for the tax hike this is a fraction 3/16 out of the 400 I'm going to I'm going to pause a recording real quick just because someone wants to join in deposit and go back to my room and I'll be right back okay okay so we're back to the recording so yeah so what we did was we took the fraction of the people that were for the tax 3 * the total number of people that were surveyed in order to determine what fraction of the people surveyed supported the tax hike question number 20 reads A Taylor has yards of shirt fabric how many shirts can she complete so then your life complete must be important if if he requires 2 3/4 yards of fabric so for this one we can actually save ourselves some time by converting a fraction into a decimal and so in order to do that is all you have to do is go to your calculator and the fraction part is 3 / 4303 / which is 75 or 3/4 which is 75 red 20 yd and it's going to take her so since you were doing in the calculus going to 20 / 2.75 2.75 and if you should get 7.27 2727 but the key word here is complete right so complete would be the whole number which is the southern right here what's a quick way to do it is just convert when you have when you have familiar fractions like 1/2 or 3/4 or 1/4 you can convert that into 15.75 or 2.25 quickly just because they're familiar fractions and once you convert a you can just type it directly into the calculator as a decimal I get around to that way oh you want to go to this one again she has 20 yards and I need to divide that 2 3/4 right and so what I did on on the calculator was all I did was divided or convert 3/4 into 2.75 Ray and then I just stopped in to calculator and we we got 7.27 to 7 to 7 but the key word here was how many she complete so she can complete seven of them and these would be the incomplete the 2727 she can only complete seven shirts does that make sense so just to 3 / 4 x 4 and then you added to see if we wanted to do it by hand in solving I just ingested quicker alternative and this one we just divide 3 by 4 and the way that we did the ones up above can we go 4 * 2 + 3 + 11/4 and then do our division where we do 20 / 1 / 11 / 4 message so question 21 reads an insurance agent estimate that it takes 2 2/3 of an hour to process a customer's claim if the agent spends 22 hours per week about how many claims does he process in a week okay no response 22 hours per week processing claims right that the total amount of time it takes 2/3 of an hour to process one claim so we need to figure out how many claims does the process per week to visit total amount of time 22 and we're going to go ahead and what do guys think is this a division or multiplication Christmas Vacation no that's what's going on Friday 2/3 until we got you can multiply 44 / 3 and then we can go ahead how many times does 3 go into 44 Legos in 14 soundtrack I can do this one what the remainder of 3 right I'm sorry with a remainder of 2 so we have 14 + 2/3 right did I make sense tickets for Less hours for me that's what's on the office well then we don't need to convert all we need to do is just it's just whatever fracture they give us all we need to do is just multiply it times the total number of hours to figure out how many claims she processes so to start from the beginning we have we have 22 total hours that this person spends working right that's a nice 22 hours and it takes him 2/3 of an hour to process one claim * * this out because every fraction is always less than 1 so 2/3 is less than 1 write so you want to know how many times how many times does the key word is in the sentence right how many * * * is is this person able to process a claim in 22 hours REI so it's a it's a multiplication it's it's a total amount of time what time is the fraction of time that it takes her to process one clean so then I go but this 1 and then I can go ahead I'm sorry I'm so sorry I just realized they can't be multiplication this is why because it takes her less than an hour to process the claim right so if she's if she has 22 hours she has to process at least 22 or more claims is that make sense everything for less than an hour 2/3 of an hour to write with less than an hour to process one so has to be at least more than 22 is if she does one an hour then shoot through 22 total claims at the end of Route 22 hours so this is a division division happens sometimes so it's 22 divided Vine 2/3 this is place over one and we do our zig zags we go 22 * 3 66 1 * 2 is and then we have 33 as an answer stomach flu Morristown trade it's messed up 1 hour yeah yeah that's what, I once we are done with it and we had an answer for those that wait a second. Doesn't seem right today's temperature so now I are flannel flushing a fluorescent lighting panel is 12 and 5/8 of an inch wide if three panels if the panels are installed as shown below what will be the width in inches of the combined panels okay so we can do we can add 12 + 5/8 + 12 + 5/8 + 12 and 5/8 or we can do 12 and 5/8 * 3 right because there's three of those panels so let's do that it'll be a lot quicker so we have 12 and 5/8 * 3 and I can just place it over one and then this I can convert it right I go eight times 12 8 * 12 + 5 + 96 + 101 / 8 * 3/1 anachronism play straight across 3038 South / 8 and then I can go in and say how many times does 8 go into there goes in three times Lancome so now I have 30 * 37 as a whole number I move down and I have seven of the numerator and I have 8 as my denominator so it's see right here and that concludes this session for math boot camp we basically went over division application and we went over to ways of doing our division and some more problems so thank you for joining us.

Uploaded by Daniel Gomez.

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