General Intelligence & Reasoning Ability for DSSSB PRT
This section has 20 questions and checks whether you can spot a pattern faster than you can calculate. Expect both verbal items (series, analogies, coding, blood relations, direction sense, syllogism, ranking) and non-verbal items (mirror and water images, paper folding, embedded figures, dice, figure series).
Core rules to keep ready
- Alphabet positions: A=1 to Z=26. The EJOTY ladder (E=5, J=10, O=15, T=20, Y=25) saves time.
- Opposite letters sum to 27: A–Z, B–Y, C–X; the reverse position of a letter is 27 minus its forward position.
- Coding–decoding usually means a fixed shift, reverse alphabet, or position-wise addition of letters.
- Blood relations: draw a family tree with clear symbols; mark gender only when stated.
- Direction sense: sketch each turn; net displacement often needs Pythagoras.
- Syllogism: test only what the statements force; 'some' is reversible, 'all' is not.
Worked example
Find the next term: 7, 12, 19, 28, 39, ? Step 1: differences are 5, 7, 9, 11 - consecutive odd numbers, so the next difference is 13. Step 2: 39 + 13 = 52. Cross-check with a second pattern: 7 = 2² + 3, 12 = 3² + 3, 19 = 4² + 3, so the next term is 7² + 3 = 52. Both routes agree, which is the confidence signal you want before marking an option.
Traps that cost marks
- Applying 'all A are B' backwards to conclude 'all B are A'.
- Direction questions where the person turns left or right while facing south - redraw rather than assume.
- Series with two interleaved patterns (alternate terms) or a square/cube base.
- Ignoring words like 'only', 'at least', 'definitely' in syllogism conclusions.
- Mirror image flips left–right; water image flips top–bottom.