Machine-translated by Google. Questions are authored in English.
Top

Discussion

Consider the following information: A person starts from point 'O'

RowMovement PatternHow far from OFinal Direction from start
14 m East → 3 m South7 mEast
2.8 m North → 15 m West17 mNorth-West
3.6 m South → 8 m East10 mWest

In how many of the above rows is/are the given information correctly matched?

  • A.Only one
  • B.Only two
  • C.All three
  • D.None

Answer: A

Only one row is correctly matched.

Each pair of perpendicular moves forms a right triangle, so the distance from O is the hypotenuse.

\[ \begin{aligned} \text{Row 1} &: \sqrt{4^2 + 3^2} = 5 \text{ m, South-East} \\ \text{Row 2} &: \sqrt{8^2 + 15^2} = 17 \text{ m, North-West} \\ \text{Row 3} &: \sqrt{6^2 + 8^2} = 10 \text{ m, South-East} \end{aligned} \]

Row 2 is fully right. Row 1 adds the legs (7 m) instead of using Pythagoras and gives East instead of South-East. Row 3 has the distance right but the direction wrong: 6 m South then 8 m East leaves the person South-East of O, not West.

No comment is present. Be the first to comment.
Loading…

Post your comment

Please log in or register to post a comment.