Aptitude - Height and Distance - Discussion
Discussion Forum : Height and Distance - General Questions (Q.No. 1)
1.
Two ships are sailing in the sea on the two sides of a lighthouse. The angle of elevation of the top of the lighthouse is observed from the ships are 30° and 45° respectively. If the lighthouse is 100 m high, the distance between the two ships is:
Answer: Option
Explanation:
Let AB be the lighthouse and C and D be the positions of the ships.
Then, AB = 100 m, 
ACB = 30° and ADB = 45°.
| AB | = tan 30° = | 1 |  AC = AB x 3 = 1003 m. |
| AC | 3 |
| AB | = tan 45° = 1 AD = AB = 100 m. |
| AD |
 CD = (AC + AD) |
= (1003 + 100) m |
| = 100(3 + 1) | |
| = (100 x 2.73) m | |
| = 273 m. |
Discussion:
104 comments Page 11 of 11.
Raksha said:
1 year ago
Why are we using tan 30°? Please explain to me.
(1)
Pooja said:
7 months ago
Simple explanation:
The formula of tan; θ is,
tan θ = opposite side/adjacent side
So, we have angles 30° and 45° and the opposite side 100 m.
So, we can find an adjacent side.
The formula of tan; θ is,
tan θ = opposite side/adjacent side
So, we have angles 30° and 45° and the opposite side 100 m.
So, we can find an adjacent side.
(1)
Bharath said:
5 months ago
We use tan because we know tan is opp by the adjutant.
The opp value is 100 which means the height of the lighthouse, we should know the distance between the two ships so we want the adjacent side.
The opp value is 100 which means the height of the lighthouse, we should know the distance between the two ships so we want the adjacent side.
(3)
Sakshi said:
2 months ago
The right answer is 273m.
(1)
Post your comments here:
Quick links
Quantitative Aptitude
Verbal (English)
Reasoning
Programming
Interview
Placement Papers