This is a combinations problem.
The total number of possible 2-item combinations is (1000 choose 2)
The number of 2-defective combinations is (300 choose 2)
The probability =
For this case we must find the surface area of a rectangular prism.
We have then:

Where,
w: width
l: long
h: height
Substituting values we have:
Answer:
There will be needed 88 in ^ 2 of giftwrap to cover the box
Answer: Real world problem is "A student have c toffee he distribute
th part of those toffees to his friends. He gave total 21 toffees to his friend".
Explanation:
Let a student have c number of toffees in his bag.
It is given that he distribute
th part of those toffees to his friends.
The
th part of c toffees is,

The total number of distributed toffees is 21.

It is the same as given equation.
If we change the equation in words it means the
th part of a number c is 21.
Step-by-step explanation:
a) 7!
If there are no restrictions, answer is 7! as it is the permutation of all animals.
b) 4! x 3!
As cats are 6 and Dogs are 5, thus 1st and last must be cats in order to have alternate arrangements. Therefore the only choices are the order of the cats among themselves and the order of the dogs among themselves. There
are 4! permutations of the cats and 3! permutations of the dogs,
so there are a total of 4! x 3! possible arrangements of the suites.
c) 3! x 5!
There are 3! possible arrangements of the dogs among themselves. Now, if we consider the dogs as one ”object” together, then we can think of arranging the 4 cats together with this 1 additional object. There are 5! such arrangements possible, so there are a total of 3! · 5! possible arrangements of the suites.
d) 2 x 4! x 3!
As required that all the cats must be together and all the dogs must be together, either the cats are all before the dogs or the dogs are all before the cats. There are two possible arrangements thus two times of both possibilities is the answer i.e. 2 x 4! x 3!