It is currently 23 Aug 2019, 15:05

### 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

# a/2 is b% of 30, and a is c% of 50. b is positive.

Author Message
TAGS:
Founder
Joined: 18 Apr 2015
Posts: 7791
Followers: 145

Kudos [?]: 1597 [0], given: 7061

a/2 is b% of 30, and a is c% of 50. b is positive. [#permalink]  29 Apr 2019, 01:42
Expert's post
00:00

Question Stats:

40% (00:36) correct 60% (01:17) wrong based on 20 sessions
$$\frac{a}{2}$$ is b% of 30, and a is c% of 50. b is positive.

 Quantity A Quantity B b c

A)The quantity in Column A is greater.
B)The quantity in Column B is greater.
C)The two quantities are equal.
D)The relationship cannot be determined from the information given.
[Reveal] Spoiler: OA

_________________
Moderator
Joined: 03 Apr 2019
Posts: 110
Followers: 1

Kudos [?]: 78 [1] , given: 1

Re: a/2 is b% of 30, and a is c% of 50. b is positive. [#permalink]  01 May 2019, 17:00
1
KUDOS
Given :
a/2=b/100*30; a = 0.6*b
A= c/100*50= 0.5*c
B = a/0.6
C= a/0.5
C is greater.
Intern
Joined: 11 Jun 2019
Posts: 6
Followers: 0

Kudos [?]: 2 [0], given: 2

Re: a/2 is b% of 30, and a is c% of 50. b is positive. [#permalink]  16 Jun 2019, 09:32
You sure this is correct?

What I got:

a/2 = (30 * b)/100; // because we are taking b% of 30 which is 30 * (b / 100). Why this is incorrect?

a = (50 * c)/100;

c = (3 * b) / 10 = 0.3 * b; => c > b.

Where I am mistaken?

Thank you!
Founder
Joined: 18 Apr 2015
Posts: 7791
Followers: 145

Kudos [?]: 1597 [0], given: 7061

Re: a/2 is b% of 30, and a is c% of 50. b is positive. [#permalink]  16 Jun 2019, 10:59
Expert's post
Translation

$$\frac{a}{2} = \frac{b}{100} \times 30$$

$$\frac{a}{2} = \frac{3b}{10}$$

$$10a=6b$$

$$5a=3b$$

$$b=\frac{5a}{3}$$

Then we do have

$$a= \frac{c}{100} \times 50$$

$$a = \frac{c}{2}$$

$$c = 2a$$

$$b = \frac{5a}{3} < c =2a$$

if you plug numbers, no matter what b is the answer
_________________
Re: a/2 is b% of 30, and a is c% of 50. b is positive.   [#permalink] 16 Jun 2019, 10:59
Display posts from previous: Sort by