In this article, we will go through with some of the important tricks that we can be used to solve Ratio and proportions problem. In quantitative aptitude, questions from Ratio and proportions are certainly asked in form of MCQs. These questions can be solved easily, if one knows the tricks.
Let’s jump into basics first
Ratio: It defines the relationship between two things which shows how many times a thing is corresponding to another thing. For example,1:2
Proportion: It defines two ratios are equal to each other. Each quantity such as A,B,C,D are known as terms.
A proportion can be divided into two categories, means, and extremes
So, the initial and last one is extremes and inbetween them are means.
Which implies, product of extremes are equivalent to product of means -> AD = BC
When a,b,c terms are related to one another ( having same unit ), then they are known as continuous proportion:
i.e a : b :: b : c
These are some of the properties of proportion:
Componendo-dividendo rule is one of the properties of proportion. It reduces the complexity of solving questions related to fractions.
According to this, if a/b = c/d
Then, ( a+b/a-b)= (c+d/c-d)
Also Read: Chain Rule Problems, Direct & Indirect Proportion
Simply means, (a*b):(b*b):(b*c)
Q. If a:b = 2:4 and b:c = 4:10 then find a:b:c?
a:b = 2:4
b:c = 4:10
then, (2*4):(4*4):(4*10)
8:16:40
Simply means, (a*b*c):(b*b*c):(b*c*c):(b*c*d)
Q. If a:b = 2:4 and b:c = 4:10 and c:d = 3:5 then find a:b:c:d?
a:b= 2:4
b:c =4:10
c:d=3:5
abc:bbc:bcc:bcd
24:48:120:200
Q. If 2X=3Y:5Z then find X:Y:Z?
Taking n as a constant
so, 2X=3Y:5Z = n
Now, getting individual quantities
2X=n
X=n/2,
Similarly,
Y=n/3
Z=n/5
X:Y:Z
n/2:n/3:n/5
1/2:1/3:1/5
When you get the answer, in this situation find the lcm of the denominator and multiply it to eliminate the fraction
So LCM of 2,3,5 is 30
30(1/2):30(1/3):30(1/5)
15:10:6
This post was last modified on July 4, 2022