Bank PO Questions

NH3, Ammonia is a neutral compound as the individual oxidation numbers elements that make up the compound NH3 are Nitrogen (N) and Hydrogen (H) sum to zero. 

We do not speak of the oxidation number of a molecule. We can speak of the oxidation numbers of the individual elements that make up the compound.

Here the oxidation number of Nirogen is -3 and that of Hydrogen is +1.

Now, NH3 = 1(-3) + 3(+1) = -3 + 3 = 0.

The hands of a clock coincide 11 times in every 12 hours (Since between 11 and 1, they
coincide only once, i.e., at 12 o'clock).

The hands overlap about every 65 minutes, not every 60 minutes.
The hands coincide 22 times in a day.

Since 653xy is divisible by 5 as well as 2, so y = 0.
Now, 653x0 must be divisible by 8.
So, 3x0 must be divisible by 8. This happens when x = 2
x + y = (2 + 0) = 2.

We know that Cubes with no surface painted can be find using x-23, where x is number of cuttings. Here x=6.

 ∴ 6-23=64

The number of exhaustive outcomes is 36.
Let E be the event of getting an even number on one die and an odd number on the other. Let the event of getting either both even or both odd then = 18/36 = 1/2
P(E) = 1 - 1/2 = 1/2.

Given equation is  

  192.5 ×19p = 197   

Here it is in the form of am × an = am+n  

 Here m = 2.5 , n = p, m+n = 7

 => 2.5 + p = 7 

 => p = 7 - 2.5

 => p = 4.5

let the radius of the pool be Rft

Radius of the pool including the wall = (R+4)ft

Area of the concrete wall = πR+42-R2=πR+4+RR+4-R = 8πR+2 sq feet

=> 8πR+2 = 1125πR2 =>11R2 =200R+2

Radius of the pool R = 20ft

As month begins on Saturday, so 2nd, 9th, 16th, 23rd, 30th days will be Sundays. While 8th and 22nd days are second Saturdays. Thus, there are 7 holidays in all.

Hence, no. of working days = 30 – 7 =23