BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

If positive real numbers a,b,c are in a.p such

Expert replies
by M7MBA » Sat Dec 23, 2017 3:44 am
If positive real numbers a,b,c are in a.p such that abc=4 Then the minimum value of b is
a)2^(1/3)
b)2^(2/3)
c)2^(1/2)
d)2^(3/2)
e)2^(1/4)

The OA is the option B.

I am really confused here. Experts, could you clarify this PS question to me? Thanks in advanced.
Join the discussion
Source: — Problem Solving |

by Scott@TargetTestPrep » Sun Sep 08, 2019 5:49 am
M7MBA wrote:If positive real numbers a,b,c are in a.p such that abc=4 Then the minimum value of b is
a)2^(1/3)
b)2^(2/3)
c)2^(1/2)
d)2^(3/2)
e)2^(1/4)

The OA is the option B.

I am really confused here. Experts, could you clarify this PS question to me? Thanks in advanced.
We see that a product of the three numbers is 4. The minimum value of b occurs when all three numbers are equal. Therefore, we have a = b = c, and hence:

b^3 = 4

b = 4^(1/3) = (2^2)^(1/3) = 2^(2/3)

Answer: B

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
Join the discussion