Question

(1)Three consecutive vertices of a parallelogram are A(1,2),B(2,3) and C(8,5).Find the fourth vertex.(HINT:diagonals of a parallelogram bisect each other)
(2)Nine rotten mangoes are mixed with 30 good ones.one mango is chosen at random.what is the probability of choosing a
(a) good mango (b) rotten mango

Pls reply faaaast......................
the 1st one to answer will be given as the best answer.

Answer 1

Mid point of line joining two points: (x1 , y1) and (x2, y2)  = [(x1+x2)/2,  (y1+y2)/2 ]

Mid point of diagonal AC = [ (1+8)/2, (2+5)/2 ] =  ( 9/2, 7/2 )
Let D (x, y).
Mid point of BD = [ (2+x)/2,  (3+y)/2 ]    = mid point of AC in a parallelogram.

 hence,  2+x = 9  => x = 7
         3 + y = 7  => y = 4
so D = (7,4)
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total number of fruits = 39
good ones 30
rotten = 9
probability of choosing a good one = 30/39
     bad one = 9/39