Exponents From GMAT PREP

This topic has expert replies
User avatar
Senior | Next Rank: 100 Posts
Posts: 80
Joined: Sat Sep 15, 2012 1:07 am
Thanked: 1 times
Followed by:1 members

Exponents From GMAT PREP

by AIM TO CRACK GMAT » Sat Jun 08, 2013 6:30 am
What is equal to 2^5+2^5+3^5+3^5+3^5?


[spoiler]OA= 2^6+3^6[/spoiler]


Ill be very glad if sum1 cud xplain me how to solve this 1!

Thanks a ton!

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

by Brent@GMATPrepNow » Sat Jun 08, 2013 6:32 am
2^5 + 2^5 + 3^5 + 3^5 + 3^5 = ?

A) 5^6
B) 13^5
C) 2^6 + 3^6
D) 2^7 + 3^8
E) 4^5 + 9^5
What we really have here is an algebra question involving the combining of like terms.

First, notice that K + K = 2K
Using the same logic, 2^5 + 2^5 = 2(2^5) = (2^1)(2^5) = 2^6

Similarly, notice that M + M + M = 3M
Using the same logic, 3^5 + 3^5 + 3^5 = 3(3^5) = (3^1)(3^5) = 3^6

So, 2^5 + 2^5 + 3^5 + 3^5 + 3^5 = 2^6 + 3^6

Answer: C

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