Class 11

Math

Algebra

Permutations and Combinations

How many different signals can be made by hoisting $6$ differently coloured flags one above the other, when any number of them may be hoisted at once?

- 1956
- 1955
- 1900
- 1901

We can hoist flags $1$ to $6$,

$=_{1}P+_{2}P+_{3}P+_{4}P+_{5}P+_{6}P=1956$ ways

Hence, option 'A' is correct.