20 people meet and shake hands. The maximum number of hand
shakes possible if there is to be no ‘cycle’ of handshakes
is( a cycle of handshake is a sequence of people a1,a2,
…..ak)such that people(a1,a2),(a2,a3)…..(a(k-1),ak),(a2,a1)
shake hand is

Answer Posted / kailash

the cycle of handshake nos = 20
i.e.,(a1,a2),(a2,a3)...........(a(k-1),ak),(ak,a1).

so, to make it no cycle (or) non-continuous the handshake is
b/w only (a1,a2),(a2,a3)...............(a(k-1),ak).
so (ak,a1) will not come.

so no of handshake = 20-1
= 19.

Is This Answer Correct ?    145 Yes 10 No



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