hey guys welcome to the cat King CET daily series today we are gonna be doing
a very interesting topic called as the quantitative comparison similar to what
we have done in data sufficiency yesterday so make sure you guys you know
and watching all of the videos I hope these sessions have been really helpful
for you we've got a lot of things of vocabulary
critical reasoning visual reasoning so make sure you don't miss out any of
these videos and log on every day to check out what's coming up next all
right so let's understand the CET quantity of comparison based questions
today okay so basically a quantitative comparison is nothing but where you'll
be given two set of quantities quantity A quantity B it could be anything you
have to compare which is greater like quantity A is greater than B, B is greater
than A or both of them are equal or they cannot be a relation between the two
remember this option is that the two are not related usually does not happen when
you have both of the entities being numericals
because some of the other equation whatever you solve you would either get
an answer them to be equal or greater or less than alright so that's a very basic
thing which you need to keep in mind now let's take a couple of examples to
understand what kind of questions come in this. The first example for today
is based on your geometry okay basic formulas of geometry so you have a
circle with AB as the diameter and the length of the diameter is 4 so my first
quantity is circumference of the circle quantity B is the value of 12 so that
means I have to compare the value of circumference of circle the circle with
12 okay for people who don't know the formula of circumference of the circle
ensure you revise all your formulae of you know geometry and arithmetic because
it's very important when it comes to quantitative comparison as well as data
sufficiency questions that's going to be very helpful for you okay so
circumference of the circle by formula is given by PI D and the value of pi is
nothing but 3.14 so if I multiply I will get 3.14 into four definitely going to
be more than 12 because 3 into 4 is 12 so my answer is pretty obvious it's A is
greater than B very simple you will take less than 10 seconds for such kind of
easy questions but in the exams we may not always get such easy
questions this is to understand what the type of questions are the next two
examples which I'm going to take our actual CET based questions because you
definitely get those kind of calculation based questions okay so now let's look
at this question where it's given when you look at the question the first thing
is going to be oh my god it's so much calculations and I don't even have a
calculator in the exam so don't fret on such things because you don't have to
calculate okay you have to do approximations now thirty two point
eight I can take approximately as thirty three percent five thousand nine twenty
nine I can approximate it to six thousand okay so let's take that value
of the quantity I approximate to thirty three percent of six thousand but the
final value has to be little less than that so I've taken a minus sign there
okay now if you know conversions like 1 by 2 is 50% 1 by 3 is 33% 1 by 4 is 25
percent 1 by 5 20 percent you should be knowing all of these things ok so if
I keep that conversion in mind 33 by 0.3 is nothing but 1/3 right one-third of
6,000 is nothing but 2,000 so my value is something less than 2,000 okay now let's
come to quantity B here it is 41.6% or 5041 I'll approximate to 40 percent of
5000 okay so if I take 40,000 a 40% of 5,000 it's going to be 2,000 but it
should be something higher because I reduced the values so it becomes 2,000
plus so how sweet this is now I have one quantity a which is less than 2,000
quantity B which is greater than 2,000 so my answers pretty straightforward
answered B is greater than a ok so that's what you have to do you don't
have to calculate the exact answer just to approximations and get to the
conclusion which quantity is greater than the other one
all right let's move on to one more example and see how do well do you
understand these concepts ok now this is a very interesting example because this
talks about comparing the different quantities ok so here what we are doing
is the fractions looking at different elements now if I go by the traditional
method I'll first find the LCM and then go ahead quantity a is
I can calculate the LCM and you know go ahead with the same but quantity B it's going
to be really taxing because 27 into 97 holy shit you're going to go man doing
such kind of calculations right so remember we don't have to do
calculations now what we are going to do is we are going to just play with
fractions around okay now if you guys know if I take a fraction and I increase
its denominator so the value will decrease the final value yes correct
similarly if I decrease the numerator again the value will decrease so that's
what I'm going to do I take 13 by 27 I increase the denominator by 1 that makes
it 13 by 28 then I decrease the numerator by 1 it becomes 12 by 28 which
is going to be less than 13 by 27 correct now 12 by 28 can be solved as
written as it is nothing but 3 by 7 you remove the common element 4 okay so that
means my quantity B's first element is greater than the first element of
quantity a alright same fashion I will do with the second element which is 41
by 97, now 97 we take it ahead 241 we reduce it to 40 that makes it 40 by 100 which
is nothing but 2 by 5 correct so what I have got is that both the elements okay
13 by 27 is greater than 3 by 7 41 by 97 is greater than 2 by 5 that means my
final answer is going to be B is greater than A that's it all I have done is
played around with fractions without any calculations LCM all of them cross
multiplication nothing to be done alright so remember this is what you
have to do play around with fractions with equations to approximations that's
all you need to do nothing else in quantitative comparison you don't have
to actually calculate the answer so I hope the session has been helpful to you
all of you guys please make sure you sign up to the CET daily series don't
miss out any of the videos will be coming up further ahead also with a lot
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and we'll make sure we take up all the feedback ahead and work on those topics
as well also all right all the best to well