Answer:
32760 ways
Step-by-step explanation:
There are overall 15 students from which we have to select 4 students at random for the 4 Cash prizes.
i) First Prize can be distributed in [tex]^{15}\textrm{C}_{1}[/tex] ways .
Also here we know the identity which says that
[tex]^{m}\textrm{C}_{1}=m[/tex]
Hence [tex]^{15}\textrm{C}_{1}=15[/tex]
Now we are left with 14 students for second prize.
ii) Second prize can be distributed in [tex]^{14}\textrm{C}_{1}=14[/tex] ways
Now we are left with 13 students for third prize.
iii) Third prize can be distributed in [tex]^{13}\textrm{C}_{1}=13[/tex] ways.
Now we are left with only one prize and which can be distributed among 12 Students
iv) Fourth prize can be distributed in [tex]^{12}\textrm{C}_{1}=12[/tex] ways.
Hence total number of ways of distributing 4 prizes among 15 students is
[tex]15 \times 14\times 13\times 12[/tex]
= 32760