|
|
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.
29 Jun 2021, 03:45
Kudos
Bookmarks
B
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
85%
(hard)
Question Stats:
52% (02:33) correct
48%
(02:16)
wrong
based on 162
sessions
History
Date
Time
Result
Not Attempted Yet
A person saves Rs. 200 more each year than in the previous year. If he started with Rs. 400 in the first year, how many years would he take to save Rs. 18,000 (excluding interest)?
(A) 10 years
(B) 12 years
(C) 15 years
(D) 18 years
(E) None of these
(A) 10 years
(B) 12 years
(C) 15 years
(D) 18 years
(E) None of these
30 Jun 2021, 19:37
Kudos
Bookmarks
Bunuel
This is a problem of Arithmetic progression:
First term = a = Rs. 400, common difference = d = Rs. 200, Total sum = S = Rs. 18,000, Number of years = n =?
\(S = \frac{n}{2} * [2a + (n - 1) * d]\)
=> \(18000 = \frac{n}{2} * [800 + 200n - 200]\)
=> \(18000 = n * [300 - 100n]\)
=> \(n^2 - 3n + 180 = 0\)
Solving above equation, we get n = 15 or n = -12
As n is years, it cannot be negative.
=> n = 15 years.
So, correct answer is option C.
03 Jul 2021, 01:11
Kudos
Bookmarks
MarmikUpadhyay
the equation will be
=> \(n^2 + 3n - 180 = 0\)
Solving above equation We get n=-15 or n =12
So n=12years (years cannot be negative)
So, correct answer is option B.[/quote]
