Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:
Re: If 18 is 15 percent of 30 percent of a certain number, what [#permalink]
13 Apr 2015, 05:33
Hello from the GMAT Club BumpBot!
Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).
Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
The math involved in this question can be 'set up' (and dealt with) in a variety of ways.
Here, if you're going to take a calculation-based approach, converting the percents to fractions would likely help you speed up (and avoid the last bit of math).
We're told that 18 is 15 percent of 30 percent of a certain number. We're asked for that number.
18 = (.15)(.3)(X)
18 = (3/20)(3/10)(X)
18 = (9/200)(X)
Since 9/200 is a relatively small fraction (it's far less than 10%), we know that 18 is LESS than 10% of X. Based on the given answer choices, there's only one number that is LARGE enough to fit that description....