SSC CGL 2020: Quantitative Aptitude
SSC CGL new vacancy 2020 has been out.
One of the most scoring topics for SSC CGL 2020 is quantitative aptitude.
Mock test in Hindi can also help you to practice more and score well.
Percentage (%) is a fraction or ratio where denominator is 100.
1. n% of x means
( x * n)/100
Example: 20% of 150 is (20*150)/100 =30
2. n% of x= x% of n
Example: 20% of 5= 5% of 20
3. find what percentage of x is n
(n / x)*100
4. If x is increased/decreased by n, then percentage
x (1+ n/100)
5. Percentage change in value= (change/initial value)*100
6. If price of a commodity increased/decreased by N%, then
change in consumption without changing the expenditure
(N/ (100 + N)) * 100 %
7. If the Population (P) is increasing with rate R% annually
Population after n years = P*(1 + R/100) n
Population before n years = P/ (1 + R/100 ) n
8. If price (P) of a commodity depreciates R% annually then,
Price of commodity after n years = P*(1 - R/100) n
Price of commodity n years ago = P/ (1 - R/100) n
SSC CGL 2020: Ratio and Proportion
Ratio(x/y) is the relation between two or more values of same
kind. Where x is antecedent and y is consequent.
- In ratio order is important. For example: x: y is not same
as y: x.
- If same number is multiplied or divided in each term of
ratio, then ratio will remain unchanged.
- Proportion (::) is when ratio of first and second element is equal
to third and fourth element.
A: B= C: D
For example: 4:10:: 8: 20=2/5
- Fourth Proportional (D) = (B*C)/ A
- If second term is equal to third term A: B:: B:C then,
Third proportional (C) = B 2 /A
- Mean proportional between A and B= √AB
- Duplicate ratio of A and B = A 2 : B 2
SSC CGL 2020: Speed, Distance & amp; Time
Speed in km/hr or m/sec or miles/ hr.
Distance in Km or meter or miles.
Time is in hours or minutes or seconds.
Km/hr to meter/ sec = speed in km/hr* 5/18
Meter/sec to km/hr= speed in m/sec* 18/5
1. Distance= Speed X Time
3. Time= Distance/ Speed
4. If object is moving with x and y speed, then
Average speed = (2xy)/(x + y)
5. When two objects are moving in same direction with x and
y speed then
Relative speed = difference of x and y
6. When two objects are moving in different direction with x
Relative speed= addition of x and y
7. If time taken by objects is same, then
Average speed= (x + y)/2
8. If distance covered by objects is same, then
Average speed= 2x*y/ (x + y)
9. If two people moving between two points A and Bin
opposite direction by crossing each other, then speed of
them will be:
Speed of A/ Speed of B=√Time taken by B/ Time taken by A
10. Calculation of least time taken to meet in circular race
is LCM (T1, T2, T3…… Tn) i.e. Least common Multiple.