125 ltr mixture of wine n water contains 20% water, how much more water b added to result in 25% concentration of water
pls explain how alligation technique can be used here in arun sharma ( straight line method)
hey aakrosh, for such type of problem, like (milk+water),or (wine +water) when one quantity (usually water) is added..solve the problem in terms of untouched quantity( here wine becoz it's concentration remains unchanged)
so initially, wine content was (80/100)* 125=100....equation1 now after adding water (let x liter) the concentration of wine would be (75/100)*(125+x)....equation2 equating 1 and 2 we get x=25/3....hope u find it easy...
i am lately facing some problems in DI section due to very less practice in it though my quant section is not bad.
i have purchased a book but it does not have DI section and i have spent quite a some of money... so please if any can give me the link for downloading ARUN SHARMA QUANT DI e-book, it will be a great help.
price of petrol rises by 40%, if Mr. A wants to limit is expenditure to 5% on petrol,then what should be corresponding decrease in consumption so that expenditure exceeds only by 5% {ref: ch-percentages LOD-I Ques: 6, arun sharma}
price of petrol rises by 40%, if Mr. A wants to limit is expenditure to 5% on petrol,then what should be corresponding decrease in consumption so that expenditure exceeds only by 5% {ref: ch-percentages LOD-I Ques: 6, arun sharma}
Suppose, initially A spends Rs. 100 on petrol. Now Mr. A has to spend Rs. 140 for the same quantity of petrol.
But he wants that his expenditure should increase only by 5% => New expenditure= Rs. 105
Change= 140-105=35 Hence, Net % decrease= (35/140)*100= 25%
28.5% decrease in consumption so that expenditure remains 5%.
dear its an arun sharma quant book ques, so I already knew d ans, but what I asked is 4 a solution, btw ans is 25% anywys thanks 4 d response :) hope u don't get frustated wid me asking simple LOD-I problems :((
hi Puys, I am stuck with LOD2,Number Systems Q.61. Define a number K such that it is the sum of the squares of the first M natural numbers. i.e(K = 1^2 + 2^2 +.....+M^2) where M How many values of M exist such that K is divisible by 4.
a)10 b)11 c)12 d)None of these .
Please help me with this ques and also explain what should be the approach for solving such type of ques.
hi Puys, I am stuck with LOD2,Number Systems Q.61. Define a number K such that it is the sum of the squares of the first M natural numbers. i.e(K = 1^2 + 2^2 +.....+M^2) where M How many values of M exist such that K is divisible by 4.
a)10 b)11 c)12 d)None of these .
Please help me with this ques and also explain what should be the approach for solving such type of ques.
K = M(M+1)(2M+1)/6
2M+1 is always odd.
Remaining M(M+1) should be divisible by 8. (Not 4, because there is a '6' in the denominator in the whole expression, which contains one power of 2)
Both M and M+1 cannot be divisible by 8 at the same time, coz if one is even, other will be odd. So either of these two should be div by 8
So we are lookin for no,s of the form M=8k and M+1=8k That is, all numbers of the form, M = 8k and M=8k-1 satisfy.
For k = 1 to 6, we get 6 no.s for each case, so that MSo total = 12 such no.s
hi Puys , please give the soln to the below questions rom LOD 2 ,Number Sysytems.
Q65.If you form a subset of integers chosen form between 1 to 3000, such that no two integers add to a multiple of 9. what can be the max number of elements in the subset.(Include both 1 and 3000.)
a)1668 b)1332 c)1333 d)1336
Q66.The Series of numbers (1,1/2,1/3,1/4........1/1972) is taken.Now two numbers are taken form this series (the first two) say x,y. the operation x+y+ x.y is prformed to get a consolidated number.the process is repeated.What will be the value of the set after all the numbers are consolidated into one number.
a)1970 b)1971 c)1972 d)None of these.
Q67.K is a three digit number such that the ratio of the number to the sum of its digit is least?What is the Difference between the hundreds and the tens digits of K?
a)9 b)8 c)7 d)None of these.
Please provide the detailed soln and also advice how to approch such problems ?
hi Puys , please give the soln to the below questions rom LOD 2 ,Number Sysytems.
Q66.The Series of numbers (1,1/2,1/3,1/4........1/1972) is taken.Now two numbers are taken form this series (the first two) say x,y. the operation x+y+ x.y is prformed to get a consolidated number.the process is repeated.What will be the value of the set after all the numbers are consolidated into one number.
a)1970 b)1971 c)1972 d)None of these.
Please provide the detailed soln and also advice how to approch such problems ?
Lets take 1 + 1/2 = 3/2. Now, 1.1/2 = 1/2 So, x + y + x.y = 3/2.1/2 = 2 Now, 2 + 1/3 + 2.1/3 = 3 3 + 1/4 + 3.1/4 = 4 So, as per the above pattern, answer would be 1972. Is it the OA ?
hi Puys , please give the soln to the below questions rom LOD 2 ,Number Sysytems.
Q67.K is a three digit number such that the ratio of the number to the sum of its digit is least?What is the Difference between the hundreds and the tens digits of K?
a)9 b)8 c)7 d)None of these.
Please provide the detailed soln and also advice how to approch such problems ?
Lets take 1 + 1/2 = 3/2. Now, 1.1/2 = 1/2 So, x + y + x.y = 3/2.1/2 = 2 Now, 2 + 1/3 + 2.1/3 = 3 3 + 1/4 + 3.1/4 = 4 So, as per the above pattern, answer would be 1972. Is it the OA ?
hi Puys , please give the soln to the below questions rom LOD 2 ,Number Sysytems.
Q65.If you form a subset of integers chosen form between 1 to 3000, such that no two integers add to a multiple of 9. what can be the max number of elements in the subset.(Include both 1 and 3000.)
a)1668 b)1332 c)1333 d)1336
Please provide the detailed soln and also advice how to approch such problems ?
My take: Answer: (d) 1336 Explanation: Consider numbers from 1 to 9. If you take 1, 8 is out. If you take 2, 7 is out. If you take 3, 6 is out. If you take 4, 5 is out.
So, out of 9, you can take 4 numbers i.e. numbers of form 9k+1, 9k+2, 9k+3, 9k+4. So, out of 2997 you can take 4*(2997/9)=1332 numbers You can also take 2998, 2999, 3000.
Additionaly, you can pick one number divisible by 9. So, totally you can pick 1332+3+1 = 1336 numbers.
Q65.If you form a subset of integers chosen form between 1 to 3000, such that no two integers add to a multiple of 9. what can be the max number of elements in the subset.(Include both 1 and 3000.)
a)1668 b)1332 c)1333 d)1336
Numbers of form 9k + 1, 9k + 2, 9k + 3, 9k + 4 can be part of the set and one of number of form 9k. => Total such numbers = 334 + 334 + 334 + 333 + 1 = 1336
Q66.The Series of numbers (1,1/2,1/3,1/4........1/1972) is taken.Now two numbers are taken form this series (the first two) say x,y. the operation x+y+ x.y is prformed to get a consolidated number.the process is repeated.What will be the value of the set after all the numbers are consolidated into one number.
a)1970 b)1971 c)1972 d)None of these.
Final result will be (x + 1)(y + 1)(z + 1) ..... (a + 1) - 1 = (1 + 1)(1 + 1/2)(1 + 1/3)......(1 + 1/1972) - 1 = 2(3/2)(4/3)(5/4)...(1973/1972) - 1 = 1973 - 1 = 1972
Q67.K is a three digit number such that the ratio of the number to the sum of its digit is least?What is the Difference between the hundreds and the tens digits of K?
a)9 b)8 c)7 d)None of these.
abc/(a + b + c) = 100 - (90b + 99c)/(a + b + c)
(90b + 99c)/(a + b + c) is maximum for a = 1 and b = c = 9 => difference is 0
