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A certain quantity is measured on two different scales,the R [#permalink]
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18 Feb 2013, 12:50
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A certain quantity is measured on two different scales, the R scale and the S scale, that are related linearly. Measurements on the R scale of 6 and 24 correspond to the measurements on the S scale of 30 and 60 respectively. What measurement on the R scale corresponds to a measurement of 100 on the S scale? (A) 20 (B) 36 (C) 48 (D) 60 (E) 84
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Re: A certain quantity is measured on two different scales,the R [#permalink]
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18 Feb 2013, 13:13
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Re: A certain quantity is measured on two different scales,the R [#permalink]
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18 Feb 2013, 17:50
Bunuel wrote: mun23 wrote: A certain quantity is measured on two different scales, the R scale and the S scale, that are related linearly. Measurements on the R scale of 6 and 24 correspond to the measurements on the S scale of 30 and 60 respectively. What measurement on the R scale corresponds to a measurement of 100 on the S scale?
(A) 20 (B) 36 (C) 48 (D) 60 (E) 84 As R increases by 18 (from 6 to 24), S increases by 30 (from 30 to 60). Thus increase of 18 in R corresponds to increase of 30 in S. Therefore change of 70 in S from 30 (when R is 6) to 100 must correspond to change of 70/30*18=42 in R. Hence, 100 in S corresponds to 6+42=48 in R. Answer: C. Sorry Bunuel, i didnt understand both question and concept of this! How u moved on with this?
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Re: A certain quantity is measured on two different scales,the R [#permalink]
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18 Feb 2013, 20:13
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Consider a line built on R scale.  6 24 The increase in value in R scale =246=18 points Now consider a line built on scale S. For the same increase in value, the increase in S scale is from 3060 i.e30 points(6030) So, we know that an increase of 18 points on R scale corresponds to 30 points on S scale. We need to find our what measurement on R scale corresponds to a value of 100 on S scale. an increase from 30 to 100 value on S scale= 70 points R scale S scale 18 point increase= 30 point increase ? = 70 point increase cross multiply ?=70*18/30=42 Thus, an increase of 70 points on S scale equals an increase of 42 points on R scale. So, the actual value=6+42=48 shanmugamgsn wrote: Bunuel wrote: mun23 wrote: A certain quantity is measured on two different scales, the R scale and the S scale, that are related linearly. Measurements on the R scale of 6 and 24 correspond to the measurements on the S scale of 30 and 60 respectively. What measurement on the R scale corresponds to a measurement of 100 on the S scale?
(A) 20 (B) 36 (C) 48 (D) 60 (E) 84 As R increases by 18 (from 6 to 24), S increases by 30 (from 30 to 60). Thus increase of 18 in R corresponds to increase of 30 in S. Therefore change of 70 in S from 30 (when R is 6) to 100 must correspond to change of 70/30*18=42 in R. Hence, 100 in S corresponds to 6+42=48 in R. Answer: C. Sorry Bunuel, i didnt understand both question and concept of this! How u moved on with this?



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Re: A certain quantity is measured on two different scales,the R [#permalink]
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19 Feb 2013, 10:17
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mun23 wrote: A certain quantity is measured on two different scales, the R scale and the S scale, that are related linearly. Measurements on the R scale of 6 and 24 correspond to the measurements on the S scale of 30 and 60 respectively. What measurement on the R scale corresponds to a measurement of 100 on the S scale?
(A) 20 (B) 36 (C) 48 (D) 60 (E) 84 Since there is a linear relationship between R and S....we can assume R =aS + b (or any other linear equation in terms of R and S) Now, when R= 6, S= 30....so the equation becomes 6 = 30a + b(i) When R = 24, S = 60...so the equation becomes 24 = 60a + b(ii) Solving the above two equations we get a = 3/5, b= 12...so the equation becomes R = (3/5)S  12....now put the value of S =100 in the equation...u'll get the value of R as 48...



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Re: A certain quantity is measured on two different scales,the R [#permalink]
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07 Mar 2013, 22:00
On scale R when we measure 6 and 24 we measure 30 and 60 respectively on scale S. Therefore an increase in 18 on scale R results in an increase of 30 on scale S.
90 on S (60 + 30) is equivalent to 42 (24 + 18) on R. To get 100 on S we add 10, an increase in 10 on S results in an increase of 6 on R (18*10/30).
42 + 6 = 48
Answer C



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Re: A certain quantity is measured on two different scales,the R [#permalink]
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06 Sep 2014, 23:41
mun23 wrote: A certain quantity is measured on two different scales, the R scale and the S scale, that are related linearly. Measurements on the R scale of 6 and 24 correspond to the measurements on the S scale of 30 and 60 respectively. What measurement on the R scale corresponds to a measurement of 100 on the S scale?
(A) 20 (B) 36 (C) 48 (D) 60 (E) 84 246 = 18 6030=30 18:30 > 6:10 so for every addition of 6 in R scale there will be 10 in S scale.



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A certain quantity is measured on two different scales,the R [#permalink]
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20 Mar 2017, 11:42
mun23 wrote: A certain quantity is measured on two different scales, the R scale and the S scale, that are related linearly. Measurements on the R scale of 6 and 24 correspond to the measurements on the S scale of 30 and 60 respectively. What measurement on the R scale corresponds to a measurement of 100 on the S scale?
(A) 20 (B) 36 (C) 48 (D) 60 (E) 84 6 > 24 > x 30 > 60 > 100 Through concept of gradient we can solve in less than 30 seconds. (246)/(6030)=(x24)/(10060) ==>x=48



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A certain quantity is measured on two different scales,the R [#permalink]
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16 Aug 2017, 00:49
when R increased from 6 to 24 ie an increase of 18 points Than S increased from 30 to 60 ie 30 points. There is a relationship between increase in R and than subsequent increase in S. This relationship can be represented as increase in S/R=30/18=5/3 Which means that for every increase in the point of R their will be 5/3 increase in the points of S. The question asks if S is 100 than what is R. S has moved from 60 to 100 a increase of 40 points When S has increased by 40 than let R increase=X we now have a relationship X*5/3=40 or X=24 Original R=24. Therefore we have 24+24=48



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Re: A certain quantity is measured on two different scales,the R [#permalink]
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06 Jan 2018, 05:33
mun23 wrote: A certain quantity is measured on two different scales, the R scale and the S scale, that are related linearly. Measurements on the R scale of 6 and 24 correspond to the measurements on the S scale of 30 and 60 respectively. What measurement on the R scale corresponds to a measurement of 100 on the S scale?
(A) 20 (B) 36 (C) 48 (D) 60 (E) 84  Since the scales R & S are linearly related we can use y=mx+c, which can be use S=m*R+c substitute the values (R,S) (6,30) (24,60) to get values of m = 5/3 & c=20 now for S = 100, find R in this equation , 100=(5/3)*R + 20 => R=48



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Re: A certain quantity is measured on two different scales,the R [#permalink]
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25 Feb 2018, 16:31
Hi All, The answer choices to this question are 'spread out' enough that you can use a bit of logic to estimate the correct answer. We're told that the relationship between the values on the RScale and SScale are LINEAR, which means that as one value increases, the other value will increase by a fixed amount. We're then told the relationship between the RScale and SScale for two sets of values (6 and 30; 24 and 60). Notice how that when the Rscale value increases from 6 to 24 (an increase of 18), the Sscale value increases from 30 to 60 (an increase of 30). The question asks for the relative Rscale value when the Sscale value is 100. Since an increase of 30 on the Sscale = an increase of 18 on the Rscale, when we go from 60 to 100 on the Sscale, we're increasing by 40 (a little more than 30)....so the increase on the Rscale should be a little more than 18.... 24 + (a bit more than 18)..... = a bit more than 42.... There's only one answer that matches: Final Answer: GMAT assassins aren't born, they're made, Rich
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Re: A certain quantity is measured on two different scales,the R [#permalink]
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07 Mar 2018, 11:12
Let linear relation be S = mR + C, where m is slope, C is Sintercept (when R = 0) Given: 30 = 6m + C (when R = 6, S = 30) 60 = 24m + C (when R = 24, S = 60) solving for m and C, we get m = 30/18, C = 20 S = (30/18)R + 20 when S = 100, R = 48




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