i have posted the question cphill you can solve it if you want :P
that was what the answer was though... 420
i am going to post my own question; i can probably solve it on my own but i will post it anyway
LOLOLOLOLOLOLOLOL
yep!!
there are 10c2 or 45 games total
and there are 5c2 or 10 games where it is boy-v-boy
so it is 10/45 or 2/9
HOPE THIS HELPED!
thank you!!!
yw!!
after x months, plant a grows 10x centimeters, and after x months, plant b grows x(x+1)/2 because of the formula for triangluar numbers. this means those two are equal, so 10x=x(x+1)/2 or 20x=x(x+1), which means 20=x+1 so x=19.
for this to be true, x^2+a and ax are equal at only one point. that means that x^2-ax+a's discriminant is 0, which means a^2-4a is 0. that means a is 0 or 4, and the sum is 4.