Question

How many different signals can be given using any number of flags from 6 flags of different colours?

• A. 1240
• B. 1956
• C. 3976
• D. 1976

Answer 1

The correct option is B 1956

The signals can be made by using at a time one or two or three or four five or six flags out of 6 different coloured flags.
$\therefore$ Required number of flags
${=}^6{P}_1{+}^6{P}_2{+}^6{P}_3{+}^6{P}_4{+}^6{P}_5{+}^6{P}_6=6+30+120+360+720+720=1956$