Exams

Let last digit is 2
when second last digit is 4 remaining 4 digits can be filled in 120 ways, similarly second last digit is 6 remained 4 digits can be filled in 120 ways.
so for last digit = 2, total numbers=240

Similarly for 4 and 6
When last digit = 4, total no. of ways =240
and last digit = 6, total no. of ways =240
so total of 720 even numbers are possible.

Now as per question, Karan invested for 12 months and Satish invested for 7 months.

So, Karan:Satish = (29000 x 12):(18000 x 7)

= 348:126

= 58:21

Satish Ratio in profit will be= 16970×2179 = Rs. 4511

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.

Area of the sheet = 20×30cm2  

Area used for typing = 20-4×30-6cm2   

required % =384600×100=64%