Product is multiplying. when you multiply a letter with a number you don't put any symbols so it would be 8c
There are a lot of vertical angles in this figure, I will try my best to list most of them; ace,bcg bca, ecg gfd,afe gfe, dfa
U should know the area of rectangle is w*l
if we increase it by double or times 2 its area will be
A=2w*2wl
A=4wl
area would be 4 times of original one
Now u can get the answer
(a) there are 8C2 = 28 ways of picking 2 girls from 8
And there are 21C4 = 5985 ways of picking 4 boys
Required number of ways for 2g / 4b = 28 * 5985 = 167,580
(b) at least 2 girls means combinations of 2g/4b , 3g,3b , 4g/2b , 5g 1b or
6 girls.
2g/4b = 167,580 ways
3g/3b = 8C3 * 21C3 = 56 * 1330 = 74,480
4g/2b = 8C4* 21C2 = 70 * 210 = 14,700
5g 1b = 8C5* 21 = 56*21 = 1176
6 girls = 8C6 = 28
adding these up we get the answer to (b) which is 257,964
The first part is 1325
10 x 35=350
15 x 65=975
The you add them which equals 1325
