Events & Promotions
|
|
GMAT Club Daily Prep
Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.
Customized
for You
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Apr 2808:00 AM PDT
-11:00 AM PDT
Whether you are just beginning your MBA journey or fine-tuning your path to a 700+ score, GMAT Day is designed to give you a competitive edge.
Apr 2711:00 AM EDT
-12:00 PM EDT
Prefer video-based learning? The Target Test Prep OnDemand course is a one-of-a-kind video masterclass featuring 400 hours of lecture-style teaching by Scott Woodbury-Stewart, founder of Target Test Prep and one of the most accomplished GMAT instructors
Apr 2912:30 AM EDT
-01:30 AM EDT
Learn how Kamakshi achieved a GMAT 675 with an impressive 96th %ile in Data Insights. Discover the unique methods and exam strategies that helped her excel in DI along with other sections for a balanced and high score.
Apr 3001:30 AM EDT
-02:30 AM EDT
At one point, she believed GMAT wasn’t for her. After scoring 595, self-doubt crept in and she questioned her potential. But instead of quitting, she made the right strategic changes. The result? A remarkable comeback to 695. Check out how Saakshi did it.
May 0111:00 AM PDT
-12:00 PM PDT
Free- full-length test + 15 concept videos + 150+ short videos + study plan!
May 0306:30 AM PDT
-08:30 AM PDT
Verbal trouble on GMAT? Fix it NOW! Join Sunita Singhvi for a focused webinar on actionable strategies to boost your Verbal score and take your performance to the next level.
01 Jul 2020, 23:02
Kudos
Bookmarks
C
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
55%
(hard)
Question Stats:
63% (02:26) correct
37%
(02:21)
wrong
based on 84
sessions
History
Date
Time
Result
Not Attempted Yet
The top of a 15 metre high tower makes an angle of elevation of 60° with the bottom of an electronic pole and angle of elevation of 30° with the top of the pole. What is the height of the electric pole?
A. 5 metres
B. 8 metres
C. 10 metres
D. 12 metres
E. 13 metres
Let AB be the tower and CD be the electric pole.
\(∠ACB=60∘ , ∠EDB=30∘ , AB=15\)
\(Let BE=AB−AE=15−h\)
\(\frac{AB}{AC}=tan 60∘= \sqrt{3}\)
=>\(AC=\frac{AB}{\sqrt{3}}\)
=>\(AC=\frac{15}{\sqrt{3}}\)
Also,
\(\frac{BE}{DE}=tan 30∘=\frac{1}{\sqrt{3}}\)
=>\(DE=BE\sqrt{3}=\sqrt{3}(15−h)\)
AC = DE
=> \(\frac{15}{\sqrt{3}} = \sqrt{3}(15−h)\)
=> \(15 = 45 - 3h\)
=> \(3h = 30\)
=> \(h = 10\)
Hence, OA is (C).
\(∠ACB=60∘ , ∠EDB=30∘ , AB=15\)
\(Let BE=AB−AE=15−h\)
\(\frac{AB}{AC}=tan 60∘= \sqrt{3}\)
=>\(AC=\frac{AB}{\sqrt{3}}\)
=>\(AC=\frac{15}{\sqrt{3}}\)
Also,
\(\frac{BE}{DE}=tan 30∘=\frac{1}{\sqrt{3}}\)
=>\(DE=BE\sqrt{3}=\sqrt{3}(15−h)\)
AC = DE
=> \(\frac{15}{\sqrt{3}} = \sqrt{3}(15−h)\)
=> \(15 = 45 - 3h\)
=> \(3h = 30\)
=> \(h = 10\)
Hence, OA is (C).
Attachments
answer.jpg [ 7.15 KiB | Viewed 8801 times ]
01 Jul 2020, 23:27
Kudos
Bookmarks
Explanation:
Check Figure below for better understanding:
∠ACB = 60 , ∠EDB = 30 , AB=15 , AC=DE
BE = AB − AE =15−h
AB/AC=tan60 = √3
AC=15/√3
BE/DE= tan30 = 1/√3
DE=√3*(15−h)
As AC = DE
15/√3 = √3*(15−h)
15 = 45 - 3h
h = 30/3
h = 10
IMO-C
Check Figure below for better understanding:
∠ACB = 60 , ∠EDB = 30 , AB=15 , AC=DE
BE = AB − AE =15−h
AB/AC=tan60 = √3
AC=15/√3
BE/DE= tan30 = 1/√3
DE=√3*(15−h)
As AC = DE
15/√3 = √3*(15−h)
15 = 45 - 3h
h = 30/3
h = 10
IMO-C
Attachments
File comment: Attachement
height.jpg [ 7.15 KiB | Viewed 8523 times ]
