a,b,c, and d are positive numbers. If ab = c and a/b = d, what is a+b?
a) dsqrt(cd)
b) sqrt(cd)/d
c) (sqrt(cd) + d)/d
d) d(sqrt(cd)+1)/d
e) (sqrt(cd)(d+1))/d
thanks.
5-Day Free Trial
5-day free, full-access trial TTP
Available with Beat the GMAT members only code
MORE DETAILS
can anyone show how to solve this algebraically?
This topic has expert replies
-
topspin330
- Junior | Next Rank: 30 Posts
- Posts: 19
- Joined: Sun Dec 11, 2011 9:04 am
-
topspin330
- Junior | Next Rank: 30 Posts
- Posts: 19
- Joined: Sun Dec 11, 2011 9:04 am
-
pemdas
- Legendary Member
- Posts: 1085
- Joined: Fri Apr 15, 2011 2:33 pm
- Thanked: 158 times
- Followed by:21 members
find (a+b)?
b=c/a and a^2=cd (from ab* a/b)
b+sqroot(a^2)=c/sqroot(cd) +sqroot(cd)= (c+cd)/sqroot(cd)=
sqrt(c)*[sqroot(c)+d*sqroot(c)]/sqroot(cd)= sqroot(c)*(1+d)/sqroot(d)= sqroot(cd)*(1+d)/d
e
b=c/a and a^2=cd (from ab* a/b)
b+sqroot(a^2)=c/sqroot(cd) +sqroot(cd)= (c+cd)/sqroot(cd)=
sqrt(c)*[sqroot(c)+d*sqroot(c)]/sqroot(cd)= sqroot(c)*(1+d)/sqroot(d)= sqroot(cd)*(1+d)/d
e
topspin330 wrote:a,b,c, and d are positive numbers. If ab = c and a/b = d, what is a+b?
a) dsqrt(cd)
b) sqrt(cd)/d
c) (sqrt(cd) + d)/d
d) d(sqrt(cd)+1)/d
e) (sqrt(cd)(d+1))/d
thanks.
Success doesn't come overnight!
