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Comment on w and k are Integers
This question is not clear to
Can you please explain?
In the expression 3400w, the
In the expression 3400w, the variable w does not represent a digit (or digits in your example). For more on this, watch: https://www.greenlighttestprep.com/module/gre-algebra-and-equation-solvi...
The variable w represents a value that is MULTIPLIED by 3400. In other words, 3400w is equal to 3400 TIMES some number (called w)
So, if w = 42; then k = (3400)(42)/(2)(2)(5)(7)(17)
= 142800/2380
= 60
I solved the question by
Answers a) through d) were all not whole integers. Ex- C) was 3400(34) 115,600/ 2380=48.57 while the only answer choice which divided as a whole integer was E) 142,800/2380= 60
That works too! :-)
That works too! :-)
Hi Brent ,
I found one of the similar question but in different way
please help me in the approach
if I just change the question as
k=3400w/2*2*5*7*17
so we get 2380/3400w
as the last digit of the numerator is 0 ,
we should find a number that is divisible by 2,5,10
is this the right approach
Thanks
That approach can (and did)
That approach can (and did) yield unintended results.
For this question I strongly recommend that you find a prime factorization of 3400, and then eliminate some prime factors from the numerator and denominator (as I did in the solution)
k = 3400w/(2)(2)(5)(7)(17)
= (2)(2)(2)(5)(5)(17)(w)/(2)(2)(5)(7)(17)
= (2)(5)(w)/(7)
From here we can see that, in order for k to be an integer, it must be the case that w is a multiple of 7.
For this reason the correct answer is E, since 42 is the only answer choice that is a multiple of 7.
Very good question. I solved