|
|
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.
20 Apr 2021, 05:15
Kudos
Bookmarks
B
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
5%
(low)
Question Stats:
90% (00:48) correct
10%
(00:45)
wrong
based on 42
sessions
History
Date
Time
Result
Not Attempted Yet
When it was 10 days old, a baby elephant ate 5 candies. From then onwards, its appetite grew, and each day it ate twice the number of candies it had eaten the previous day. How many candies did the baby elephant eat when it was 14 days old?
(A) 40
(B) 80
(C) 100
(D) 120
(E) 130
(A) 40
(B) 80
(C) 100
(D) 120
(E) 130
29 Apr 2021, 03:55
Kudos
Bookmarks
Bunuel
Days - Candies
\(10\hspace{2mm} - \hspace{2mm}5\)
\(11\hspace{2mm} - \hspace{2mm}10\)
\(12 \hspace{2mm}- \hspace{2mm} 20\)
\(13\hspace{2mm}- \hspace{2mm} 40\)
\(14\hspace{2mm} - \hspace{2mm} 80\)
Or one could use G.P
\(n^{th}\) term of a G.P = \(ar^{n-1}\)
Here \(a= 5,\hspace{2mm} r=2\) and \(n= 5\)
\(5*2^4 = 80\)
Ans-B
Hope it's clear.
24 May 2021, 10:11
Kudos
Bookmarks
Bunuel
Solution:
Since the baby elephant ate twice as many candies as it did the previous day, when the baby elephant was 11 days old, it ate 10 candies. When it was 12 days old, it ate 20 candies. When it was 13 days old, it ate 40 candies. Finally, when it was 14 days old, it ate 80 candies.
Alternate Solution:
The scenario described is a geometric sequence, with first term a = 5, r = 2 (doubling), and n = 14 - 10 + 1 = 5. We use the formula for the nth term of a geometric sequence: y = ar^(n - 1) as follows:
y = ar^(n - 1)
y = (5)(2^4)
y = (5)(16) = 80
Answer: B
