Doubt & Answer Explanation

Doubt

 1. the number of ordered triplets of positive integers which are the solutions of the equation x y z=100 is
a)5081 b)6005 c)4851 d)6273.

2. the number of ways in which Rs 20  can be distriuted among five children such that no one receives than Rs 3 is
a)125 b)126 c)127 d)128.

 3. ²ⁿC₃ :ⁿC₂ =11 :1 then n is
a)5 b)4 c)6 d)8.

4. the number of different words ending and begining with a consonant which can be made out of the letters of the word EQUATION is
a)5200 b)4320 c)1295 d)3000.

5. the number of different words that can be formed out of the letters of the word MORADABAD taken four a time is
a)500 b)600 c)620 d)626.

6. numbers lying between 99 and 1000 can be formed from the digits2,3,7,0,8,6 are
a)100 b)150 c)200 d)250.

 7. how many triangles can be drawn through n given points on a cricle?