If (1 – 1.25)N = 1, then N =

This topic has expert replies
Source: — Problem Solving |

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 16207
Joined: Mon Dec 08, 2008 6:26 pm
Location: Vancouver, BC
Thanked: 5254 times
Followed by:1268 members
GMAT Score:770

Re: If (1 – 1.25)N = 1, then N =

by Brent@GMATPrepNow » Tue Aug 25, 2020 9:05 am
BTGModeratorVI wrote:
Thu Aug 20, 2020 7:08 am
If (1 – 1.25)N = 1, then N =

(A) −400
(B) −140
(C) −4
(D) 4
(E) 400


Answer: C
Source: Official guide
(1 – 1.25)N = 1
Simplify to get: -0.25N = 1
Rewrite as (-1/4)N = 1
Multiply both sides by -4 to get: N = -4

Answer: C

Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
Image

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 8086
Joined: Sat Apr 25, 2015 10:56 am
Location: Los Angeles, CA
Thanked: 43 times
Followed by:29 members
BTGModeratorVI wrote:
Thu Aug 20, 2020 7:08 am
If (1 – 1.25)N = 1, then N =

(A) −400
(B) −140
(C) −4
(D) 4
(E) 400


Answer: C
Source: Official guide
Solution:

We can simplify the given equation:

(1 – 1.25)N = 1

-0.25N = 1

N = 1/(-0.25)

N = -4

Answer: C

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