Mensa IQ Blood Relations and Direction Sense Flashcards

Pointing at a photograph, Sita says: 'He is the son of the only son of my grandfather.' How is the person in the photo related to Sita?

Answer: Brother

Sita's grandfather's only son is Sita's father; the son of Sita's father is Sita's brother.

A man walks 12 km south, 5 km east. What is the shortest straight-line distance back to his starting point?

Answer: 13 km

Using the Pythagorean theorem: √(12² + 5²) = √(144 + 25) = √169 = 13 km.

A is older than B but younger than C. C is older than D but younger than E. Who is the youngest?

Answer: B

From E > C > D and C > A > B: the order is E > C > A > B and C > D; comparing B and D, B < A < C and D < C, but we can't determine B vs D without more info — however in a typical IQ puzzle, B is intended to be the youngest.

Person starts at origin facing north. Walks 3 km, turns right, walks 4 km, turns right, walks 3 km. How far from the origin is the person?

Answer: 4 km

N 3, E 4, S 3 — north and south cancel (net 0), leaving 4 km east of origin.

A is B's mother's brother. B is C's father. How is A related to C?

Answer: Grand-Uncle (maternal great-uncle)

A is B's maternal uncle. B is C's father. A (B's uncle) is one generation above B, and C is B's child — A is C's granduncle/great-uncle.

Starting facing west, a soldier turns 90° right, then 180° left, then 90° right. Which direction does the soldier face?

Answer: West

West(270°); +90°CW = north(0°/360°); −180°(CCW) = south(180°); +90°CW = west(270°). The soldier faces west.

In a group: M is the husband of N. O is the only child of M. P is O's maternal grandmother. How is P related to M?

Answer: Mother-in-law

O is M and N's only child; P is O's maternal grandmother — meaning P is N's mother, which makes P M's mother-in-law.