General Mental Ability · HCS (Haryana)

What the official syllabus says

CSAT (Preliminary Examination, Paper II):
General mental ability.

Topics in detail

Verbal reasoning

Number series, letter series and alphanumeric series: missing and wrong terms
Analogies: words, letters and numbers
Classification: finding the odd one out
Coding and decoding: letter shifts, number codes, substitution, symbols
Blood relations, including coded relations and family trees
Direction sense and distance: turns, shadows, final position
Order and ranking: position from the left and the right, from the top and the bottom
Alphabet test: positions of letters, words in dictionary order
Mathematical operations with replaced symbols
Word formation and arrangement of words in a meaningful order

Calendars and clocks

Odd days; the day of the week for a given date; leap years
Angle between the hands of a clock; times when the hands coincide or are opposite
Gaining and losing clocks

Venn diagrams and sets

Representing relations between classes (for example: doctors, women, graduates)
Counting from overlapping sets

Non-verbal reasoning

Figure series and figure analogies
Mirror images and water images
Paper folding and paper cutting
Embedded figures and completing a figure
Counting triangles, squares and lines in a figure
Dice: opposite faces from several positions
Cubes: painted cubes cut into smaller cubes

Approach

Learning standard patterns (squares, cubes, primes, alternate terms, positions of letters)
Using diagrams for direction and blood-relation questions
Timed practice, since these questions reward speed and accuracy

Facts worth knowing

Topic	Fact
Calendar	An ordinary year has 1 odd day; a leap year has 2
Calendar	A century year is a leap year only if divisible by 400 (2000 was, 1900 was not)
Clock	The minute hand moves 6 degrees a minute; the hour hand 0.5 degree a minute
Clock	Angle between the hands at H hours M minutes = the difference of 30H and 5.5M
Clock	The hands coincide 11 times in 12 hours (22 times in a day)
Dice	In a standard die, the numbers on opposite faces add up to 7
Alphabet	Positions: A=1, E=5, J=10, O=15, T=20, Y=25; reverse position = 27 minus position

How to practise

Most questions here follow a small number of patterns. Working through each type until the pattern is recognised at sight, and then practising mixed sets against time, builds the speed this section needs.

Overlaps

"General Mental Ability" is also a topic of Prelims General Studies (Paper I), where, in the gazette's words, "the candidates will be tested on reasoning and analytical abilities". Preparation for one serves both papers. See also Logical Reasoning and Analytical Ability.