Statement 1: P(T at least once in N trials)

case one n=4:

T occurs once . So it will be=1/4*3/4*3/4*3/4= 27/256.

T occurs twice so it will be= 1/4*1/4*3/4*3/4 = 9/256

T occurs three times so it will be= 1/4*1/4*1/4*3/4 = 3/256

T occurs four times so it will be= 1/4*1/4*1/4*1/4 = 1/256

so the sum = 27+9+3+1/256 = 40/256 <1/2 and the answer will be always less than 1/2 as we move to big number

5,6,7,..........so on. Statement 1 is suff

Statement 2: N could be 1,2,3,4,5

case one N=1 T occurs once = 1/4 <1/2

case 2 N=2

T occurs once= 1/4*3/4= 3/16

T occurs twice=1/4*1/4=1/16. So, 1/16+3/16= 4/16 = 1/8<1/2

case 3 N=3

T occurs once= 1/4*3/4*3/4= 9/64

T occurs twice=1/4*1/4*3/4= 3/64

T occurs tree times 1/4*1/4*1/4= 1/64. So, 9+3+1/64= 13/64<1/2

and so on the case for N=4,5 so statment 2 is also suff.

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