Question

Consider the word $W=MISSISSIPPI$.

If $N$ denotes the number of different selections of $5$ letters from the word $W=MISSISSIPPI$ then $N$ belongs to the set,

• A. $\{15,16,17,18,19\}$
• B. $\{20,21,22,23,24\}$
• C. $\{25,26,27,28,29\}$
• D. $\{30,31,32,33,34\}$

Answer 1

The correct option is B $\{20,21,22,23,24\}$

In $MISSISSIPPI$

$M=1I=4S=4P=2$

$5$ letters word can be made as:-

${}^2{C}_1{}^3{C}_1{+}^2{C}_1{+}^2{C}_1^3{C}_2{+}^3{C}_1\times 1$

$=6+4+6+6+3$

$=23$

the set is $\{20,21,22,23,24\}$