Giri

The marks obtained by a number of students in a certain subject are approximately normally distributed with mean 65 and standard deviation 5. If 3 students are selected at random from this group, what is the probability that at least 1 of them would have...

The random variable X has probability density function f(x)={ax+bx2 , 0<x<1 . If E(X)=0.6 , find (a)P(X<1/2) and (b)var(x).

An oil tank in the shape of a right circular cylinder with horizontal axis is filled to a depth of 3 feet. If the circular ends of the tank have diameters of 10 feet and the length of the tank is 12 feet, how many cubic feet of oil are in the tank?

I think B is correct.

Everything is correct above except for the last. It is divide and not multiply. To get the seconds =(L/4.7) Also look the units Liter get cancelled and only seconds remain.

Recycling the trash helps environment and ofcourse less pollution (as you mentioned).

60 cats

You meant DC? It is Sqroot(25^2 - 15^2) = 20

Google and find the formula. slope of line from (x1,y1) and (x2, y2) is slope= (y2-y1)/(x2-x1) (x2 Not Equal x1)

Given-The dimensions of the room equal to 5m.And the carpet covers 60% of the area of the room. Soln-That is area of the room is 25sq.m That gives, 60% of room = 60÷100(25) =15 sq.m That's the dimension of carpet is 15m