Telephone Call

This topic has expert replies
Master | Next Rank: 500 Posts
Posts: 431
Joined: Sat Jan 10, 2009 9:32 am
Thanked: 16 times
Followed by:1 members

Telephone Call

by kanha81 » Mon Jun 01, 2009 11:31 am
The charge for a telephone call between City R and City S is $0.42 for each of the first 3 minutes and $0.18 for each additional minute. A certain call between these two cities lasted for x minutes, where x is an integer. How many minutes long was the call?

(1) The charge for the first 3 minutes of the call was $0.36 less than the charge for the remainder of the call.

(2) The total charge for the call was $2.88.

I could not understand or setup an equation for the (1). Please help!
Want to Beat GMAT.
Always do what you're afraid to do. Whoooop GMAT

Master | Next Rank: 500 Posts
Posts: 322
Joined: Fri Mar 27, 2009 3:56 pm
Thanked: 24 times
GMAT Score:710

by mike22629 » Mon Jun 01, 2009 11:47 am
IMO D.

Info in Passage:
.42$ per minute for first 3 minutes, so 1.26$ for first 3 minutes.
Each additional minute .18

Statement 1:)
Since the charge for the first 3 minutes of the call was .36 less than the remainder
Total Cost = 1.26 + (1.26 + .36) = 2.88
1.62/.18 + 3 = total minutes

Notice I did not calculate actual answer because it is not necessary.

Master | Next Rank: 500 Posts
Posts: 431
Joined: Sat Jan 10, 2009 9:32 am
Thanked: 16 times
Followed by:1 members

by kanha81 » Mon Jun 01, 2009 11:58 am
mike22629 wrote:IMO D.

Info in Passage:
.42$ per minute for first 3 minutes, so 1.26$ for first 3 minutes.
Each additional minute .18

Statement 1:)
Since the charge for the first 3 minutes of the call was .36 less than the remainder
Total Cost = 1.26 + (1.26 + .36) = 2.88
1.62/.18 + 3 = total minutes

Notice I did not calculate actual answer because it is not necessary.
Mike,
To be honest, I quite did not get your deduction of total cost. Trivial as it may see, I am not able to understand. Can you please help me understand this?
mike22629 wrote: Total Cost = 1.26 + (1.26 + .36) = 2.88
1.62/.18 + 3 = total minutes
Want to Beat GMAT.
Always do what you're afraid to do. Whoooop GMAT

Master | Next Rank: 500 Posts
Posts: 171
Joined: Mon Jun 01, 2009 8:59 pm
Thanked: 8 times

D

by brick2009 » Mon Jun 01, 2009 9:32 pm
Answer : D

a.) if X is the total minutes,
(x-3)x18 cent = (3x.42)-.36 ...so you can solve for X

b.) is straight forward

Legendary Member
Posts: 1169
Joined: Sun Jul 06, 2008 2:34 am
Thanked: 25 times
Followed by:1 members

by aj5105 » Tue Jun 02, 2009 6:29 am
Statement (1) : 1.26 + 0.36 = 0.18 * C [C = each additional minute over 3]

Sufficient


Statement (2) :1.26 + 0.18 * C = 2.88

Sufficient

[D]

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 7222
Joined: Sat Apr 25, 2015 10:56 am
Location: Los Angeles, CA
Thanked: 43 times
Followed by:29 members

by Scott@TargetTestPrep » Tue Dec 05, 2017 5:28 pm
kanha81 wrote:The charge for a telephone call between City R and City S is $0.42 for each of the first 3 minutes and $0.18 for each additional minute. A certain call between these two cities lasted for x minutes, where x is an integer. How many minutes long was the call?

(1) The charge for the first 3 minutes of the call was $0.36 less than the charge for the remainder of the call.

(2) The total charge for the call was $2.88.
We are given that the charge for a telephone call between City R and City S is $0.42 for each of the first 3 minutes and $0.18 for each additional minute. We are also given that a call between the two cities lasted for x minutes. We can create the following equation:

3(0.42) + 0.18(x - 3) = total cost of the call

1.26 + 0.18x - 0.54 = total cost of the call

0.18x + 0.72 = total cost of the call

We must determine the value of x.

Statement One Alone

The charge for the first 3 minutes of the call was $0.36 less than the charge for the remainder of the call.

Using the information in statement one, and from the given information, we can create the following equation:

1.26 = (0.18x - 0.54) - 0.36

0.78 = 0.18x - 0.54

2.16 = 0.18x

x = 12

Statement one alone is sufficient to answer the question. We can eliminate answer choices B, C, and E.

Statement Two Alone

The total charge for the call was 2.88.

Using the information in statement two, and from the given information, we can create the following equation:

0.18x + 0.72 = $2.88

0.18x = $2.16

x = 12

Answer: D

Scott Woodbury-Stewart
Founder and CEO
[email protected]

Image

See why Target Test Prep is rated 5 out of 5 stars on BEAT the GMAT. Read our reviews

ImageImage