GMAT Question of the Day - Daily to your Mailbox; hard ones only

 It is currently 22 Feb 2019, 16:46

### 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

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

## Events & Promotions

###### Events & Promotions in February
PrevNext
SuMoTuWeThFrSa
272829303112
3456789
10111213141516
17181920212223
242526272812
Open Detailed Calendar
• ### Free GMAT RC Webinar

February 23, 2019

February 23, 2019

07:00 AM PST

09:00 AM PST

Learn reading strategies that can help even non-voracious reader to master GMAT RC. Saturday, February 23rd at 7 AM PT
• ### FREE Quant Workshop by e-GMAT!

February 24, 2019

February 24, 2019

07:00 AM PST

09:00 AM PST

Get personalized insights on how to achieve your Target Quant Score.

# By what percent was the price of a smartphone increased? (1) The price

Author Message
TAGS:

### Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 53066
By what percent was the price of a smartphone increased? (1) The price  [#permalink]

### Show Tags

09 Oct 2018, 02:19
00:00

Difficulty:

15% (low)

Question Stats:

97% (00:31) correct 3% (00:25) wrong based on 39 sessions

### HideShow timer Statistics

By what percent was the price of a smartphone increased?

(1) The price of the smartphone was increased by $40. (2) The price of the smartphone after the increase was$400.

_________________
Manager
Joined: 22 Jan 2018
Posts: 54
Location: India
Concentration: Operations, Technology
GMAT 1: 650 Q44 V35
GPA: 4
By what percent was the price of a smartphone increased? (1) The price  [#permalink]

### Show Tags

09 Oct 2018, 02:31
Bunuel wrote:
By what percent was the price of a smartphone increased?

(1) The price of the smartphone was increased by $40. (2) The price of the smartphone after the increase was$400.

percentage increase = ( Change in price/ old price ) * 100

1- price increased by 40
let the original price be X
new price is X+40
Percentage increase = (40/X)*100 we can't get value out of it.
Statement -1 Not Sufficient

2- new price =400
Old price= X
percentage increase = (400-X/X)*100 we can't get value out of it.
statement-2 not sufficient

Combining Statement 1 and 2:-

New price = 400
Price increased by = 40
Old price = 400-40 = 360
Hence, percentage increase = (40/360)*100 | we got a value

Correct answer should be - C

Give Kudos, if it helped.
Director
Joined: 19 Oct 2013
Posts: 508
Location: Kuwait
GPA: 3.2
WE: Engineering (Real Estate)
Re: By what percent was the price of a smartphone increased? (1) The price  [#permalink]

### Show Tags

09 Oct 2018, 04:29
Bunuel wrote:
By what percent was the price of a smartphone increased?

(1) The price of the smartphone was increased by $40. (2) The price of the smartphone after the increase was$400.

we want to know the percentage change = $$\frac{New - old}{old} *100$$

1)
Say the old price was a
the new price will be a+40

$$\frac{a+40 - a}{a} = \frac{40}{a}$$ this will depend on the value of a, if it is 80 then 50% increase, if a is 100 then it is 40% increase.

Insufficient

2) we are given that a+increase = 400

$$\frac{400 - a}{a}$$ it does not provide information on the old value.

Combine (1) and (2)

We get $$a + 40 = 400$$

a = 360

$$\frac{400 - 360}{360} = \frac{40}{360} = \frac{1}{9}*100 = 11.11$$

Manager
Joined: 09 Jun 2018
Posts: 189
Location: United States
GPA: 3.95
WE: Manufacturing and Production (Energy and Utilities)
Re: By what percent was the price of a smartphone increased? (1) The price  [#permalink]

### Show Tags

09 Oct 2018, 07:40
Stmt 1: Gives only change in value. Initial value/final value missing. Hence insufficient.
Cross out A and D

Stmt 2: Gives only final value. Change or initial value, one of the two required. Hence insufficient.
Cross out B

Stmt 1 and Stmt 2: Final value given, change given. So initial value can be calculated. Percentage can be found as 100*(change/initial). Sufficient.

Hence C.

No need to actually calculate values since it is DS!
_________________

If you found this relevant and useful, please Smash that Kudos button!

Re: By what percent was the price of a smartphone increased? (1) The price   [#permalink] 09 Oct 2018, 07:40
Display posts from previous: Sort by