Suppose there are n people in the party. The first person shakes hand with the other (n-1) guests. The second guest shakes hand with the other (n-2) guests. this will continue until the (n-1) th guest shakes hand with the nth guest.
Total number of handshakes is (n-1) + (n-2)... + 3 + 2 + 1.
= ((n-1)(n))/2
For example, 6 people in a party shake hand with other guests. So how many handshakes will be there?
=((6-1)(6))/2
=15.
Code: ഇപ്പൊ ഭിക്ഷയ്ക്കു അവിടെ പോഡി .
ഇപ്പൊ ഭി - ഹെപ്പറ്റൈറ്റിസ് ബി .
ക്ഷ - ക്ഷയം .
അ - അഞ്ചാം പനി .
വി - വില്ലൻ ചുമ .
ടെ - ടെറ്റനസ് .
പോ - പോളിയോ .
ഡി - ഡിഫ്ത്തീരിയ.
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Important Maths Formulas .
(a ± b) 2 = a 2 ± 2ab + b 2 .
(a + b + c) 2 = a 2 + b 2 + c 2 + 2(ab + bc + ca).
(a + b + c + d) 2 = a 2 + b 2 + c 2 + d 2 + 2(ab + ac + ad + bc + bd + cd) .
Geometry formulas .
Perimeter ( ചുറ്റളവ് ) .
Perimeter of a square: P=4a.
a: length of one side.
Perimeter of a rectangle: P=2(l+w).
l: length.
w: width.
Perimeter of a triangle: P=a+b+c.
a, b, and c: lengths of the 3 sides.
Area ( വിസ്തീര്ണ്ണം ) .
LINE_FE...
Permutation and combination related questions are common in PSC and Bank exams.
Before going to Combinations and Permutations, first lean about factorial. .
If n is a positive integer then, factorial of n is denoted as n! . .
4! = (1 x 2 x 3 x 4 ) = 24.
Permutations are for lists of items, whose order matters and combinations are for group of items where order doesn’t matter. in other words, .
When the order of items doesn\\\'t matter, it is called as Combination.
When the order of items does matter it is called as Permutation.
The number of permutations of n objects taken r at a time is determined by using this formula:.
C(n,r)=n!/((n−r)!r!) .
Combination : Picking a team of 3 people from a football coaching group of 10. C(10,3) = 10!(3!(10−3)!) = 120. ....