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How many multiples of 3 are there between 9 and 99

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How many multiples of 3 are there between 9 and 99

by uptowngirl92 » Thu Jul 16, 2009 9:06 pm
How many multiples of 3 are there between 9 and 99 inclusive?
options:30 31 32 33 34
Ans 31

Here's where I am getting stuck:
3 x 3 =9
3 x 33 =99
Since the question asks for "including" there are 33-3+1=31 numbers.The solution ends here,but I went furthur and substracted 2 more (for 3x1 and 3x2.ofcourse because such an option was notthere I realised my mistake and "guessed the correct answer.)
Can somebody tell me when the last step is reqd.?Because I clearly remember doing such a problem where the last step was reqd.!
Thnx!
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My way may help you....

by struggling_guy2001 » Thu Jul 16, 2009 9:18 pm
Hi ,

It is clear from the statement that, 3*33 = 99. Hence, there lies 33 multiples of 3 from 1-99.

As the question is from 9-99, if you remove 3 and 6 we can get the answer as 31.

I hope it would be fine if you subtract 2 from 33 as the question asks to find multiples from 9. ( i.e subtracting 3 and 6).

I think it might help you to find out mistake in your answering.

Hope it is clear...........
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by tohellandback » Thu Jul 16, 2009 9:34 pm
(99-9)/3 + 1=31 Answer
remember, always check the last value of the range if it is divisible add 1
if not then do not add anything, just subtract and divide
ex: how many even numbers between 1 and 9
(9-1)/2=4
how many even numbers between 2 and 10 inclusive
(10-2)/2 + 1=5
Last edited by tohellandback on Thu Jul 16, 2009 9:42 pm, edited 1 time in total.
The powers of two are bloody impolite!!
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Uptown....

by struggling_guy2001 » Thu Jul 16, 2009 9:36 pm
Hi,
FYI.. 29 would be the exact answer if 9 and 99 are exclusive...
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Re: Uptown....

by tohellandback » Thu Jul 16, 2009 9:44 pm
struggling_guy2001 wrote:Hi,
FYI.. 29 would be the exact answer if 9 and 99 are exclusive...
but the question says that they are inclusive..
and of course you can subtract 2 if they are not..
The powers of two are bloody impolite!!
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by Scott@TargetTestPrep » Mon Sep 02, 2019 5:53 pm
uptowngirl92 wrote:How many multiples of 3 are there between 9 and 99 inclusive?
options:30 31 32 33 34
https://www.beatthegmat.com/how-many-mu ... 40907.html

How many multiples of 3 are there between 9 and 99 inclusive?

A. 30
B. 31
C. 32
D. 33
E. 34

Solution:

The number of multiples of 3 between 9 and 99 inclusive is:

(99 - 9)/3 + 1 = 90/3 + 1 = 31

Answer: B

Scott Woodbury-Stewart
Founder and CEO
[email protected]

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