Quantitative Aptitude - Arithmetic Ability Questions

Assume that the number is taken as XYZ.
Condition 1 => Z = sq.root(x) => Possible digits of X is 1,4,9
Condition 2 => Y = X + Z
X Y Z
1 2 1
4 6 2
9 12 3 => (wrong because it is 4 digit.)

and 121 is not divisible by 2

The answer is 462.

10C5 x 28C1 x 10C6 = 7266

Sol : In this kind of questions we find the work force required to complete the work in 1 day (or given unit of time) then we equate the work force to find the relationship between the efficiencies (or work rate) between the different workers.

Therefore, 6B+8G = 6 days

 => 6(6B+8G)= 1 day  (inversely proportional)

 => 36B+48G =1         ( by unitary method)

Again  14B+10G = 4days

 => 56B+40G =1

so, here it is clear that either we employ 36B and 48G to finish the work in 1 day or 56B and 40G to finish the same job in 1 day. thus , we can say

 => 36B+48G = 56B+40G

 => G= 2.5B

Thus a Girl is 2.5 times as efficient as a boy.

Now, since  36B+48G = 1

 => 36B+48(2.5 B)=1

 =>156B=1

i.e., to finish the job in 1 day 156 boys are required or the amount of work is 156 boys-days

Again    1G+1B=2.5B+1B=3.5B

Now, since 156 boys can finish the job in 1 day

so 1 boy can finish the job in 156 days

Therefore, 3.5 boys can finish the job in 1×1563.5= 47 days.

K's 1 day's salary = 1/10
L's 1 day's salary = 1/15
Together their 1 day's salary = 1/10 + 1/15
= 3/30 + 2/30
= 5/30
= 1/6
So the money will be enough for paying them both for 6 days.

Probability is Number of favourable outcomes by total outcomes

Total comes = 2 (Divisible or not)

Favourable = 1 (Divisible)

Hence, probability = 1/2.

As per divisibility rule a number is divisible by 6 means it should be divisible by 2 and 3

case 1 : the divisibility rule for 2 is the number should be end with even number
in this case R =2 & R=4

case 2 : The divisibility rule for 3 is the sum of numbers should be divisible by 3
so if we take option (2) Q=1 & R=4 the sum is 39
if we take option (3) Q=1 & R=2 the sum is 37

So Option (2) is correct 39 is divided by 3

As water costs free, water sold at cost price of milk gives the profit.

Required profit % = 5/20 x 100 = 5 x 5 = 25%.

Given the company has 8 SD + 6 SRP + 7 IN = 21 cars + 'x' small cars.
Given SD makes 1/4 th of the total fleet.
=> 8 = 1/4 (21 + x)
=> 32 = 21 + x
=> x = 11
Therefore, the company has 11 small cars.