sana.noor wrote:The s subjects in an experiment are divided into 4 groups: 3 test groups and a control. If each group is further divided into units consisting of u subjects each, with each unit assigned to a different researcher, how many researchers are assigned to units?
(A) s/u
(B) u/s
(C) 3s/u
(D) 4s/u
(E) 4u/s
A
The trick here is that you don't need the "4 groups" part at all.
Since "each unit is assigned to a different researcher", we just need to find the number of "units". To find that, the "breaking into four groups" step is unnecessary. (In fact, you can't use that step -- even if you want to -- because there's no information about the sizes of the groups. In particular, there are no grounds for assuming that the 4 groups contain equal numbers of subjects.)
Algebraically:
There are a total of
s students.
So, if there are
u students in each unit, then the total number of units is
s/
u. Done.
Pick your own numbers:
Let there be 100 subjects total, and let
u = 5.
Then we're breaking 100 people into units of 5 people each, so that's 20 units.
Plug
s = 100 and
u = 5 into the choices: (A) 20, (B) less than 1, (C) 60, (D) 80, (E) less than 1.
So it's (a).
Ron has been teaching various standardized tests for 20 years.
--
Pueden hacerle preguntas a Ron en castellano
Potete chiedere domande a Ron in italiano
On peut poser des questions à Ron en français
Voit esittää kysymyksiä Ron:lle myös suomeksi
--
Quand on se sent bien dans un vêtement, tout peut arriver. Un bon vêtement, c'est un passeport pour le bonheur.
Yves Saint-Laurent
--
Learn more about ron
