unlike the last question you posted (the number of digits in 2^3000, which would never show up on the gmat), this one, or at least something like it, isn't unreasonable as a test question.
no, you don't have to count.
all that's important in this problem is to find the FIRST and LAST such integers.
unless you've memorized an ungodly number of perfect squares, the latter end will take a bit of experimentation, but it's easy to zero in on the desired value fairly quickly.
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the least such integer is 11^2 = 121. EVERYONE taking the gmat should know perfect squares at this level.
to find the greatest such integer, note that 30^2 = 900, so you know that you're looking for the square of a number that's "a lil bigger than 30".
try them out:
31^2 = 961
32^2 = 1024
so, looks like 31^2 is the upper end.
therefore, you're looking at all the perfect squares from 11^2 to 31^2, inclusive.
there are 31 - 11 + 1 = 21 such perfect squares.
ans (b)
Are You Going to Count?
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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
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Learn more about ron
I am surprised that you would say GMAT would never ask such a simple question as I posted in the last thread. Very surprised.lunarpower wrote:unlike the last question you posted (the number of digits in 2^3000, which would never show up on the gmat), this one, or at least something like it, isn't unreasonable as a test question.
no, you don't have to count.
all that's important in this problem is to find the FIRST and LAST such integers.
unless you've memorized an ungodly number of perfect squares, the latter end will take a bit of experimentation, but it's easy to zero in on the desired value fairly quickly.
--
the least such integer is 11^2 = 121. EVERYONE taking the gmat should know perfect squares at this level.
to find the greatest such integer, note that 30^2 = 900, so you know that you're looking for the square of a number that's "a lil bigger than 30".
try them out:
31^2 = 961
32^2 = 1024
so, looks like 31^2 is the upper end.
therefore, you're looking at all the perfect squares from 11^2 to 31^2, inclusive.
there are 31 - 11 + 1 = 21 such perfect squares.
ans (b)
