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Mary’s annual income is $15,000 and John’s annual income is [#permalink]
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04 Mar 2013, 07:50
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Mary’s annual income is $15,000 and John’s annual income is $18,000. By how much must Mary’s annual income increase so that it constitutes 55% of Mary and John’s combined income?(A) $3,000 (B) $4,000 (C) $7,000 (D) $11,000 (E) $25,000 Source: Gmat Hacks 1800
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Re: Mary’s annual income is $15,000 and John’s annual income is [#permalink]
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04 Mar 2013, 08:02
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megafan wrote: Mary’s annual income is $15,000 and John’s annual income is $18,000. By how much must Mary’s annual income increase so that it constitutes 55% of Mary and John’s combined income?
(A) $3,000 (B) $4,000 (C) $7,000 (D) $11,000 (E) $25,000
Source: Gmat Hacks 1800 Let Mary's income increase by x, then the equation will be 15,000 + x= (55/100)* (15,000 + x + 18000 ) 15,000 + x = (11/20) * (33,000 + x) 300,000 + 20x = 11x + 363,000 9 x = 63,000 x = 7,000 So, Answer will be C Hope it helps!
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Re: Mary’s annual income is $15,000 and John’s annual income is [#permalink]
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04 Mar 2013, 12:09
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megafan wrote: Mary’s annual income is $15,000 and John’s annual income is $18,000. By how much must Mary’s annual income increase so that it constitutes 55% of Mary and John’s combined income?
(A) $3,000 (B) $4,000 (C) $7,000 (D) $11,000 (E) $25,000
Source: Gmat Hacks 1800 Plug in method works for this question perfectly. Try the middle number: if Mary's annual income increase by $7,000, her income will be $22,000 and combined income will be 22,000 + 18,000 = $40,000. 55% of $40,000 is exactly $22,000. Answer: C. Hope it helps.
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Re: Mary’s annual income is $15,000 and John’s annual income is [#permalink]
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Mary’s annual income is $15,000 and John’s annual income is $18,000. By how much must Mary’s annual income increase so that it constitutes 55% of Mary and John’s combined income?
Let X be the combined income. Since only Mary's income is increasing then John's income 18000 must constitute 45% of the total income , thus 18000 = 45% of X X = 18000*100/45 X= 40000
Thus increase in Mary's income is 40000  (18000+15000) = 7000.



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Re: Mary’s annual income is $15,000 and John’s annual income is [#permalink]
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04 Feb 2014, 14:23
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megafan wrote: Mary’s annual income is $15,000 and John’s annual income is $18,000. By how much must Mary’s annual income increase so that it constitutes 55% of Mary and John’s combined income?
(A) $3,000 (B) $4,000 (C) $7,000 (D) $11,000 (E) $25,000
Source: Gmat Hacks 1800 Should they mention to constitute 55% of Mary and John combined income after the increase? Cause for me it is not 100% clear. What do you guys think about the language? Cheers J



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Re: Mary’s annual income is $15,000 and John’s annual income is [#permalink]
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Mary................. John ............... Total 15000 ................ 18000 ................... 33000 Lets say Mary's income increases by x 15000+x .............. 18000 .................... 33000+x Post increment, Mary's income should constitute 55% of total combined; this also means that John's income should constitute 45% This step helps variable "x" to be in only one side of the equation\(\frac{45}{100} (33000+x) = 18000\) x = 7000 Answer = C
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Mary’s annual income is $15,000 and John’s annual income is [#permalink]
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24 Jun 2014, 01:49
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Let Mary's income increase by x. (15000+x) /(33,000+x) = 55/100 x=7000
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Re: Mary’s annual income is $15,000 and John’s annual income is [#permalink]
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26 Mar 2015, 05:36
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megafan wrote: Mary’s annual income is $15,000 and John’s annual income is $18,000. By how much must Mary’s annual income increase so that it constitutes 55% of Mary and John’s combined income?
(A) $3,000 (B) $4,000 (C) $7,000 (D) $11,000 (E) $25,000
Source: Gmat Hacks 1800 Current ratio is \(\frac{15000}{33000} = \frac{15}{33}\) what should be added to denominator and numerator to make it \(\frac{55}{100}\) or \(\frac{11}{20}\) or \(\frac{22}{40}\) . Adding 7 will make \(\frac{15+7}{33+7}\) = \(\frac{22}{40}\) Answer 7000. C
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Re: Mary’s annual income is $15,000 and John’s annual income is [#permalink]
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28 Aug 2017, 15:19
the trick is to use 11/20 rather than 0.55, there is no secret in this question. It should not be hard at all.



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Re: Mary’s annual income is $15,000 and John’s annual income is [#permalink]
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07 Mar 2018, 12:15
Using weighted average method:
New Mary's income <4555>18K(John's)
Mary's new/Johns = 55/45 Mary's new = (11/9) * 18 = 22K so increment must , 22000  15000 = 7000




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