A little help with this problem please

[Azazel]

I have three times as many female ants as male ants. I know that the survival rate for female ants is twice as good as it is for males.
If i have 90 female ants and 12 of them die, how many male ants should be left?

theres a really long time for me and i dont remember if i am doing it right.
So, a little help would be apreciated with this xD

 

[Romsek]

I have three times as many female ants as male ants. I know that the survival rate for female ants is twice as good as it is for males.
If i have 90 female ants and 12 of them die, how many male ants should be left?

theres a really long time for me and i dont remember if i am doing it right.
So, a little help would be apreciated with this xD

At the start you have 90 female ants which is three times as many male ants.
Thus you have 90 female ants and \(\displaystyle ?_1\) male ants at the start.

Some period of time elapses and 12 female ants die
The survival rate for females is twice as good as for males so the number of male ants that die should be \(\displaystyle ?_2\)

So there are \(\displaystyle ?_1 - ?_2\) male ants left

Use what math sense you've got to figure out the two question marks. Both are just arithmetic.