I'm more visual, but if you're not, and this confuses you, ask me, and I'll explain it.
For this case we have:
10 scented markers: Column 1, row 3.
6 are permanent markers: Column 1, row 1
Half of the unscented markers are erasable: (1/2) * 30 = 15 Column 2, row 2.
Therefore, the selected table corresponds to the attached image.
Answer:
See attached image.
1+1 = 2 that is the answer
Combinations of 7 taken 4 at a time.
C (7,4) = 7! /[ 4!(3!)]
7 x 6 x 5 = 210
210 divided by 3 = 70
70 divided by 2 = 35
12 cookies= 1 dozen.
12*4 (dozens) =48
48/ 4= 12
12 cookies is a 1/4 or 25% of the whole amount of cookies.
48- 12= 36
He brings 36 cookies to school.