i think C as well,

If u consider only option 2 u get..

X1+X2+X3+X4 = 120
X3+X4 = 19

Hence x1+x2 = 91

now these two can be any number (60,31) (90,1), (59,32).. hence ur not sure how many are more than 30.

u can tell that only if know that none of the numbers are more than 60. which is option 1.

hope it helps..

is the ans C?

x1+x2+x3+x4 = 120

x3+x4 = 19

=> x1+x2 = 101

so the 2 nos can be anything even 50,51(both of which are less than 60)

or the lower limit of 41,60 which is still less than 60 and which gives us 2 nos greater than 30.

My appologies, but I'm going to ask a rather basic question; how do you get x3+x4 = 19 and x1+x2 = 101?

we have 4 nums here, x1, x2, x3, x4

stem says that the average is 30
stmt#2 says two nums are 9 and 10

so from above we get the equation:

(x1+x2+x3+x4)/4 = 30

=> x1+x2+x3+x4=120

x3+x4=19................from stmt#2