You can pick number for these problems:

Start from statement 2: g > h, no other information is given about r, s and least height.

Answer can be: A, C, E

Statement 1: r < s, let r = 8, s = 10
r = 14 - 6
s = 15 - 5 or 17 - 7

Not sufficient.

combine both the statements and pick numbers satisfying both the answer choices.
r = 8, s = 10, g = 14, h = 12
r = 14 - x1
s = 12 - x2

we know that r < s therefore, x1 is greater than x2

Thanks for the help but I got lost on the combining part. Can you please help me better understand that last part?

P.S. When I combine, I get: r < s < h < g . Is that right?

P.S.S. Maybe I'm not understanding the question stem: Is it asking 'Which of the two classes has the most shortest students'?

BlindVision wrote:Thanks for the help but I got lost on the combining part. Can you please help me better understand that last part?

P.S. When I combine, I get: r < s < h < g . Is that right?

P.S.S. Maybe I'm not understanding the question stem: Is it asking 'Which of the two classes has the most shortest students'?

you already have got the individual parts. so lets see what happens when we combine both
plug in numbers
let r=15
g=20
so least height in class A is 5
now plug in numbers for B
r<s so lets say s is 16
g>h
so lets say h=19
lest height in B is 3 i.e less than 5

Combining both, least element in ClassB has to be less than ClassA.

(C)

Ian's post:

dragonxiam- when you chose numbers here, you made r larger than s, when it should be smaller than s, which is why you've arrived at the wrong answer.

Neither statement is sufficient on its own- clearly we need to know about r, s, g and h here. Together we know:

s > r
g > h

These inequalities are in the same direction, so we can add them:

s+g > r+h
g-r > h-s

So we've shown that the smallest height in class A, which is g-r, is larger than the smallest height in class B, which is h-s. C.