Events & Promotions
|
|
GMAT Club Daily Prep
Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.
Customized
for You
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Apr 2301:30 AM EDT
-02:30 AM EDT
Struggling with GMAT Verbal as a non-native speaker? Harsh improved his score from 595 to 695 in just 45 days—and scored a 99 %ile in Verbal (V88)! Learn how smart strategy, clarity, and guided prep helped him gain 100 points.
Apr 2212:30 AM EDT
-01:30 AM EDT
At one point, she believed GMAT wasn’t for her. After scoring 595, self-doubt crept in and she questioned her potential. But instead of quitting, she made the right strategic changes. The result? A remarkable comeback to 695. Check out how Saakshi did it.
Apr 2308:00 PM PDT
-09:00 PM PDT
Video explanations + diagnosis of 10 weakest areas + 150+ short videos + study plan!
Apr 2610:00 AM EDT
-11:00 AM EDT
The Target Test Prep course represents a quantum leap forward in GMAT preparation, a radical reinterpretation of the way that students should study. Try before you buy with a 5-day, full-access trial of the course for FREE!
Apr 2711:00 AM EDT
-12:00 PM EDT
Prefer video-based learning? The Target Test Prep OnDemand course is a one-of-a-kind video masterclass featuring 400 hours of lecture-style teaching by Scott Woodbury-Stewart, founder of Target Test Prep and one of the most accomplished GMAT instructors
Apr 2808:00 AM PDT
-11:00 AM PDT
Whether you are just beginning your MBA journey or fine-tuning your path to a 700+ score, GMAT Day is designed to give you a competitive edge.
Updated on: 02 Mar 2014, 04:36
Originally posted by joemama142000 on 16 Nov 2005, 18:58.
Last edited by Bunuel on 02 Mar 2014, 04:36, edited 2 times in total.
Last edited by Bunuel on 02 Mar 2014, 04:36, edited 2 times in total.
Renamed the topic, edited the question, added the OA and moved to PS forum.
Kudos
Bookmarks
E
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
35%
(medium)
Question Stats:
77% (02:11) correct
23%
(02:41)
wrong
based on 1235
sessions
History
Date
Time
Result
Not Attempted Yet
The concentration of a certain chemical in a full water tank depends on the depth of the water. At a depth that is x feet below the top of the tank, the concentration is \(3 + \frac{4}{\sqrt{5-x}}\) parts per million, where 0 < x < 4. To the nearest 0.1 foot, at what depth is the concentration equal to 6 parts per million?
(A) 2.4 ft
(B) 2.5 ft
(C) 2.8 ft
(D) 3.0 ft
(E) 3.2 ft
(A) 2.4 ft
(B) 2.5 ft
(C) 2.8 ft
(D) 3.0 ft
(E) 3.2 ft
Every tricky question should trigger a follow up quiz.
Build that habit with
GMAT Club Forum Quiz →.
02 Mar 2014, 04:40
Kudos
Bookmarks
PeterHAllen
Given: at a depth that is x feet below the top of the tank, the concentration is \(3 + \frac{4}{\sqrt{5-x}}\) parts per million.
Question: at what depth, for which x, is the concentration equal to 6 parts per million? So, for which x, is \(3 + \frac{4}{\sqrt{5-x}}\) equal to 6?
\(3 + \frac{4}{\sqrt{5-x}}=6\) --> \(x\approx{3.2}\).
Answer: E.
Hope it's clear.
10 Feb 2018, 20:37
Kudos
Bookmarks
joemama142000
OCDianaOC
OCDianaOC - This question's wording is not easy. I rephrased it.
Given: a chemical concentration of 6
Given: a formula that will tell how deep the water is at a particular concentration, IF we have the concentration (we do)
Formula: \(3 + \frac{4}{\sqrt{5-x}}\)
Set the formula equal to concentration. The concentration of 6, in tandem with the formula, will yield depth.
\(3 + \frac{4}{\sqrt{5-x}} =\\
6\)
Subtract 3 from both sides:
\(\frac{4}{\sqrt{5-x}} = 3\)
Square both sides:
\((\frac{4^2}{(\sqrt{5-x})^2}) = 3^2\)
\((\frac{16}{(5-x)}) = 9\)
Multiply both sides by denominator and solve:
\(16 = 9(5 - x)\)
\(16 = 45 - 9x\)
\(9x = 29\)
\(x = \frac{29}{9} = 3.2\) feet
Answer E
Hope that helps.
**The language "where 0 < x < 4," is mostly irrelevant. It's to keep the denominator in the formula positive. (Can't divide by zero, can't take the square root of a negative number.)
