Question:
A scientific committee is to formed from 6 Indians and 8 foreigners, which includes at least 2 Indians and double the number of foreigners as Indians.
Then the number of ways, the committee can be formed is:
Correct Option: , 3
Solution:
$(2 \mathrm{I}, 4 \mathrm{~F})+(3 \mathrm{I}, 6 \mathrm{~F})+(4 \mathrm{I}, 8 \mathrm{~F})$
$={ }^{6} \mathrm{C}_{2}{ }^{8} \mathrm{C}_{4}+{ }^{6} \mathrm{C}_{3}{ }^{8} \mathrm{C}_{6}+{ }^{6} \mathrm{C}_{4}{ }^{8} \mathrm{C}_{8}$
$=15 \times 70+20 \times 28+15 \times 1$
$=1050+560+15=1625$