Last visit was: 22 Apr 2026, 00:29 It is currently 22 Apr 2026, 00:29
Home
Messages
Tests
Schools
Events
Close
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
Your Progress

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
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Go to My Error Log Learn more
Close
Request Expert Reply
Confirm Cancel
Back to Forum
Create Topic
505-555 (Easy)|   Algebra|         
User avatar
SimaQ
User avatar
Joined: 06 Feb 2006
Last visit: 24 May 2007
Posts: 430
Own Kudos:
649
 [21]
Posts: 430
Kudos: 649
 [21]
The equation (M + 6)/36 = (p – 7)/21 relates two temperature Updated on: 10 Oct 2013, 02:09
Originally posted by SimaQ on 19 Oct 2006, 10:32.
Last edited by Bunuel on 10 Oct 2013, 02:09, edited 1 time in total.
Edited the question and added the OA.
4
Kudos
Add Kudos
16
Bookmarks
Bookmark this Post
00:00
Start Timer
Pause Timer
Resume Timer
Show Answer
Hide
Show
History
E
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!

Difficulty:

15% (low)

Question Stats:

84% (02:09) correct 16% (02:39) wrong based on 981 sessions

History

Date
Time
Result
Not Attempted Yet
The equation (M + 6)/36 = (p – 7)/21 relates two temperature scales, where M is the number of degrees on one scale and P is the number of degrees on the other scale. Which of the following equations can be used to convert temperatures from the P scale to the M scale?

(A) M = (12/7)P + 13
(B) M = (12/7)P + 21
(C) M = (12/7)P – 12
(D) M = (12/7)P – 13
(E) M = (12/7)P – 18
ShowHide Answer
Official Answer
E
If this question felt shaky, try an adaptive mini quiz of similar problems in GMAT Club Forum Quiz →. Free plan gives 5 questions per day.
User avatar
Fig
User avatar
Joined: 01 May 2006
Last visit: 02 Feb 2025
Posts: 1,031
Own Kudos:
253
Posts: 1,031
Kudos: 253
The equation (M + 6)/36 = (p – 7)/21 relates two temperature 19 Oct 2006, 13:40
Kudos
Add Kudos
Bookmarks
Bookmark this Post
(E) if the typo 7/12 is adapted to 12/7. :)

(M+6)/36=(p-7)/21
<=> M+6 = 36*(p-7)/21
<=> M = 12/7*p - 18
User avatar
londonluddite
User avatar
Joined: 30 Aug 2006
Last visit: 28 Jan 2008
Posts: 221
Own Kudos:
292
 [2]
Posts: 221
Kudos: 292
 [2]
The equation (M + 6)/36 = (p – 7)/21 relates two temperature 19 Oct 2006, 14:48
1
Kudos
Add Kudos
1
Bookmarks
Bookmark this Post
21(M+6)=36(p-7)
21M+21(6)=36p-36(7)
3M+3(6)=36p/7 - 36
3M=36p/7 - 54
M=12p/7 - 18
avatar
darikamanee
avatar
Joined: 12 Nov 2012
Last visit: 30 Apr 2015
Posts: 1
Posts: 1
Kudos: 0
The equation (M + 6)/36 = (p – 7)/21 relates two temperature 09 Oct 2013, 19:19
Kudos
Add Kudos
Bookmarks
Bookmark this Post
I am not an expert. But this is what I get

m+6/36 =p-7/21 ----> Do cross multiply

21(m+6) = 36(p-7)
21m +126 = 36p - 252
21m = 36p - 252- 126
21m = 36p - 378
m = 36p - 378/21
m = 36p/21 - 378/21
m = 12p/7 - 18

I don't know if I did the process correctly but I got the right answer anyway.
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 21 Apr 2026
Posts: 109,740
Own Kudos:
810,514
 [1]
Given Kudos: 105,816
Products:
GMAT Club Tests Forum Quiz
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 109,740
Kudos: 810,514
 [1]
The equation (M + 6)/36 = (p – 7)/21 relates two temperature 10 Oct 2013, 02:15
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
SimaQ
The equation (M + 6)/36 = (p – 7)/21 relates two temperature scales, where M is the number of degrees on one scale and P is the number of degrees on the other scale. Which of the following equations can be used to convert temperatures from the P scale to the M scale?

(A) M = (12/7)P + 13
(B) M = (12/7)P + 21
(C) M = (12/7)P – 12
(D) M = (12/7)P – 13
(E) M = (12/7)P – 18
Show more

NOTE: EDITED THE OPTIONS.

\(\frac{M + 6}{36} = \frac{p - 7}{21}\);

\(M+6=\frac{12}{7}(P-7)\);

\(M+6=\frac{12}{7}P-12\);

\(M=\frac{12}{7}P-18\).

Answer: E.
User avatar
EMPOWERgmatRichC
User avatar
Major Poster
Joined: 19 Dec 2014
Last visit: 31 Dec 2023
Posts: 21,777
Own Kudos:
13,045
Given Kudos: 450
Status:GMAT Assassin/Co-Founder
Affiliations: EMPOWERgmat
Location: United States (CA)
GMAT 1: 800 Q51 V49
GRE 1: Q170 V170
Expert
Expert reply
GMAT 1: 800 Q51 V49
GRE 1: Q170 V170
Posts: 21,777
Kudos: 13,045
The equation (M + 6)/36 = (p – 7)/21 relates two temperature 26 Nov 2015, 16:58
Kudos
Add Kudos
Bookmarks
Bookmark this Post
HI All,

This question can be solved by TESTing VALUES. With the equation (M + 6)/36 = (p – 7)/21, we should look to make the fractions as 'simple' as possible.

When M = 30, we have...

(36)/36 = (P-7)/21

...so P = 28

Among the 5 answer choices, we're looking for one that gives us an M=30 when we plug in P=28. There's only one answer that matches...

Final Answer:
Show Spoiler
E

GMAT assassins aren't born, they're made,
Rich
User avatar
ScottTargetTestPrep
User avatar
Target Test Prep Representative
Joined: 14 Oct 2015
Last visit: 21 Apr 2026
Posts: 22,276
Own Kudos:
26,528
 [2]
Given Kudos: 302
Status:Founder & CEO
Affiliations: Target Test Prep
Location: United States (CA)
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 22,276
Kudos: 26,528
 [2]
The equation (M + 6)/36 = (p – 7)/21 relates two temperature 09 May 2019, 18:15
2
Kudos
Add Kudos
Bookmarks
Bookmark this Post
SimaQ
The equation (M + 6)/36 = (p – 7)/21 relates two temperature scales, where M is the number of degrees on one scale and P is the number of degrees on the other scale. Which of the following equations can be used to convert temperatures from the P scale to the M scale?

(A) M = (12/7)P + 13
(B) M = (12/7)P + 21
(C) M = (12/7)P – 12
(D) M = (12/7)P – 13
(E) M = (12/7)P – 18
Show more

We need to isolate M:

(M + 6)/36 = (P - 7)/21

21(M + 6) = 36(P - 7)

7(M + 6) = 12(P - 7)

7M + 42 = 12P - 84

7M = 12P - 126

M = (12/7)P - 18

Answer: E
User avatar
Mo2men
User avatar
Joined: 26 Mar 2013
Last visit: 09 May 2023
Posts: 2,426
Own Kudos:
1,508
Given Kudos: 641
Concentration: Operations, Strategy
Schools: Erasmus (II)
Products:
My Reviews
Schools: Erasmus (II)
Posts: 2,426
Kudos: 1,508
The equation (M + 6)/36 = (p – 7)/21 relates two temperature 09 May 2019, 18:38
Kudos
Add Kudos
Bookmarks
Bookmark this Post
SimaQ
The equation (M + 6)/36 = (p – 7)/21 relates two temperature scales, where M is the number of degrees on one scale and P is the number of degrees on the other scale. Which of the following equations can be used to convert temperatures from the P scale to the M scale?

(A) M = (12/7)P + 13
(B) M = (12/7)P + 21
(C) M = (12/7)P – 12
(D) M = (12/7)P – 13
(E) M = (12/7)P – 18
Show more

Another way:

(M + 6)/36 = (p – 7)/21

(M + 6)/12 = (p – 7)/7

(M + 6)/36 = (p – 7)/21

When P= 7 then M=-6

Apply in each option, only one fits

Answer: E
User avatar
Kinshook
User avatar
Major Poster
Joined: 03 Jun 2019
Last visit: 21 Apr 2026
Posts: 5,986
Own Kudos:
5,855
Given Kudos: 163
Location: India
Schools: HBS '26 CBS '26 Wharton '26
GMAT 1: 690 Q50 V34
WE:Engineering (Transportation)
Products:
My Reviews
Schools: HBS '26 CBS '26 Wharton '26
GMAT 1: 690 Q50 V34
Posts: 5,986
Kudos: 5,855
The equation (M + 6)/36 = (p – 7)/21 relates two temperature 10 May 2020, 01:43
Kudos
Add Kudos
Bookmarks
Bookmark this Post
SimaQ
The equation (M + 6)/36 = (p – 7)/21 relates two temperature scales, where M is the number of degrees on one scale and P is the number of degrees on the other scale. Which of the following equations can be used to convert temperatures from the P scale to the M scale?

(A) M = (12/7)P + 13
(B) M = (12/7)P + 21
(C) M = (12/7)P – 12
(D) M = (12/7)P – 13
(E) M = (12/7)P – 18
Show more

Given: The equation (M + 6)/36 = (p – 7)/21 relates two temperature scales, where M is the number of degrees on one scale and P is the number of degrees on the other scale.

Asked: Which of the following equations can be used to convert temperatures from the P scale to the M scale?

(M + 6)/36 = (p – 7)/21
M + 6 = 36(p-7)/21 = (12/7)(p-7) = (12/7)p - 12
M = (12/7)p - 18

IMO E
User avatar
Kinshook
User avatar
Major Poster
Joined: 03 Jun 2019
Last visit: 21 Apr 2026
Posts: 5,986
Own Kudos:
5,855
Given Kudos: 163
Location: India
Schools: HBS '26 CBS '26 Wharton '26
GMAT 1: 690 Q50 V34
WE:Engineering (Transportation)
Products:
My Reviews
Schools: HBS '26 CBS '26 Wharton '26
GMAT 1: 690 Q50 V34
Posts: 5,986
Kudos: 5,855
The equation (M + 6)/36 = (p – 7)/21 relates two temperature 10 May 2020, 01:48
Kudos
Add Kudos
Bookmarks
Bookmark this Post
SimaQ
The equation (M + 6)/36 = (p – 7)/21 relates two temperature scales, where M is the number of degrees on one scale and P is the number of degrees on the other scale. Which of the following equations can be used to convert temperatures from the P scale to the M scale?

(A) M = (12/7)P + 13
(B) M = (12/7)P + 21
(C) M = (12/7)P – 12
(D) M = (12/7)P – 13
(E) M = (12/7)P – 18
Show more

Given: The equation (M + 6)/36 = (P – 7)/21 relates two temperature scales, where M is the number of degrees on one scale and P is the number of degrees on the other scale.

Asked: Which of the following equations can be used to convert temperatures from the P scale to the M scale?

\(\frac{(M + 6)}{36} = \frac{(P – 7)}{21}; M + 6 = (\frac{36}{21})(P-7) = (\frac{12}{7})P - 12; M = (\frac{12}{7})P -18\)

IMO E
User avatar
luisdicampo
User avatar
Joined: 10 Feb 2025
Last visit: 19 Apr 2026
Posts: 480
Own Kudos:
73
Given Kudos: 328
Products:
My Reviews Forum Quiz
Posts: 480
Kudos: 73
The equation (M + 6)/36 = (p – 7)/21 relates two temperature 19 Nov 2025, 07:09
Kudos
Add Kudos
Bookmarks
Bookmark this Post
SimaQ
The equation (M + 6)/36 = (p – 7)/21 relates two temperature scales, where M is the number of degrees on one scale and P is the number of degrees on the other scale. Which of the following equations can be used to convert temperatures from the P scale to the M scale?

(A) M = (12/7)P + 13
(B) M = (12/7)P + 21
(C) M = (12/7)P – 12
(D) M = (12/7)P – 13
(E) M = (12/7)P – 18
Show more
The goal is to solve for \(M\) in terms of \(P\).

Given the equation:
\(\frac{M + 6}{36} = \frac{P - 7}{21}\)

First, multiply both sides by 36 to isolate \((M + 6)\):
\(M + 6 = \frac{36}{21}(P - 7)\)

Simplify the fraction \(\frac{36}{21}\). Both numbers are divisible by 3:
\(\frac{36}{3} = 12\) and \(\frac{21}{3} = 7\)
So, \(\frac{36}{21} = \frac{12}{7}\).

Now substitute this back into the equation:
\(M + 6 = \frac{12}{7}(P - 7)\)

Expand the right side:
\(M + 6 = \frac{12}{7}P - \frac{12}{7} \times 7\)
\(M + 6 = \frac{12}{7}P - 12\)

Finally, subtract 6 from both sides to solve for \(M\):
\(M = \frac{12}{7}P - 12 - 6\)
\(M = \frac{12}{7}P - 18\)

This matches option (E).

Answer: E
Moderators:
Bunuel
Math Expert
109740 posts
Krunaal
Tuck School Moderator
853 posts