Fwd: Questions

[Atul Nischal]

Hi,

Here are 3 questions from June 2015 CBSE NET Exam. Please provide the answer with explanation. 

1. How many strings of 5 digits have the property that the sum of their digits is 7?
A. 66
B. 330
C. 495
D. 99

2. Consider an experiment of tossing two fair dice, one black and one red. What is the probability that the number on the black die divides the number on red die ?
A. 22 / 36
B. 12 / 36
C. 14 / 36
D. 6 / 36


3. In how many ways can 15 indistinguishable fishes be placed into 5 different ponds, so that each pond contains atleast one fish?
A. 1001
B. 3876
C. 775
D. 200