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Question
A ladder makes an angle of 60° with the ground when placed against a wall. If the foot of the ladder is 2 m away from the wall, then the length of the ladder (in metres) is:
(A) `4/sqrt3`
(B) `4sqrt3`
(C) `2sqrt2`
(D)4
Solution
In the figure, MN is the length of the ladder, which is placed against the wall AB and makes an angle of 60° with the ground.
The foot of the ladder is at N, which is 2 m away from the wall.
∴ BN = 2 m
In right-angled triangle MNB:
`"Number of favourable outcomes"/"Total number of outcomes"=3/4`
Therefore, the length of the ladder is 4 m.
Hence, the correct option is D.
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