Some one please explain this concept !!
Suppose there are two tanks A and B of which, A is full of milk and B is empty. Now x liters is transferd from A to B(x
How did this come ??
after first operation concentration of milk in A is (1-x) and after second transfer it's (1-x) (1-y)
and concentration in B is 1-(1-x)(1-y) ...
Two articles are purchased at a certain price. The selling price of both the articles are identical. On the first article the profit % is 20 and on the second, the loss % is 15. Find the overall %gain/loss in the whole transaction
(1) 18% (2) 19 (3)20/41 (4) 25%
Find the remainder when 1!+2!+3!.. 47! Is divided by 20.
(1)13 (2)15 (3)17 (4)19
A batsman gets out for 10 runs in the last innings, decreasing his average by 2. If the batsman scored 19 more runs his average would have decreased by 1. Find the total runs scored by that batsman before his innings
(1)784 (2) 824 (3) 864 (4) None of these
There are two positive integers X and Y . When X is divided by 417 , the remainder is 331. When Y is divided by 83 , the quotient is the same but the remainder is 69. Find the remainder when X+Y divided by 125.
(1)25 (2)67 (3)56 (4) Can't be determined
Each edge of a cube is increased by 50%. The percentage increase in the surface area will be
(1)50% (2)125% (3)150% (4) None of these
It is given that a, b, c are non-zero distinct real numbers such that:- a + (1/b) = b + (1/c) = c + (1/a) Find the value of abc??? approach is needed not just answer 😁
An intelligence agency decides on a code of two-digit selected from 0, 1, 2, …, 9. But the slip on which the code is handwritten allows confusion between the top and bottom, because these are indistinguishable. For example, the code 91 could be confused with 16. How many codes are there such that there is no possibility of any confusion?
A) 60
B) 75
C) 80
D) 70
E) None of these
A bus 'a' left a town 'm' for another town 'n' at 5:00 am.At 6:30 am another bus 'b' left m for n and the speed of the bus is 5km/hr greater than that of 'a'. At 9:30 pm on the same day, the buses are 21km apart. Find the speed of 'a'
(1)48kmph (2)80kmph (3)72kmph (4)None of these
Answer the question on the basis of the information given below.
Four distinct non-zero single digit numbers a, b, c and d satisfy the following four conditions:
I. The sum of (b, c, d) is a multiple of 9.
II. The sum of (a, c, d) is a multiple of 8.
III. The sum of (a, b, d) is a multiple of 5.
IV. The sum of (a, b, c) is a multiple of 23.
Which number is the largest?
A)a
B)b
C)c
D)d
E)cannot be determined
How many numbers are there between 100 and 1000 such that units digit is either 2 or 9?
(1)64 (2) 75 (3)144 (4) 180
A right angled triangle of base 10 cm and height 24 cm is rotated along its hypotenuse. Find the volume of cone thus formed?
(1)1235. cu.cm (2)5776.84 cu.cm (3)2318.75 cu.cm (4) None of these
How many three-digit numbers are there, such that I. all are divisible by 55, II. the difference between the digits in the hundred's and ten's place is one more than the digit in the unit's place?
A)5B)8
C)3
D)4
E)7
If n = 1+x, where x is the product of four consecutive positive integers, then which of the following is/are true?
A. n is odd
B. n is prime
C. n is a perfect square
If a+b+c=0, then the quadratic equation 3aX^2+2bX+c=0 has
1) at least one root in (0,1)
2) one root in (2,3)and the other on (-2,-1)
3) imaginary roots
4) none of these 
Find the minimum three digit number n for which (3n + 4)/5, (4n + 5)/3 and (5n + 3)/4 are integers??
Mahesh alone can construct a wall in 15 days while ramesh can demolish the same by himself in 25 days .If mahesh starts working on a odd date,Dinesh helps him ,suresh helps ramesh only if dinesh helps mahesh .in a day,dinesh does half as much work as ramesh and suresh does half as much work as mahesh.find the minimum number of days required to build the wall if mahesh and ramesh work on alternate days .
. If a+b = 1 and a2 +b2 = 2, evaluate a4 +b4
. How many even integers between 4000 and 7000 have four different digits?
How many ordered triples (x, y, z) of non-negative integers have the property that x+y +z = 8?