It's difficult to draw a tree diagram with this software.
Try to do it yourself & you will find the followings:
If A is selected (P(A) =1/2) we can get ether red (p(A & red)=4/7
so P(A∩red)= 1/2 x 4/7 = 4/14
Also we can get P(blue) = 3/7 & P(A∩blue) = 1/2 x 3/7 = 3/14
Same reasoning for B & you will get P(B∩read) 1/2 x 3/4 = 3/8
Also we can get P(B∩blue) = 1/2 x 1/4 = 1/8
Probability of blues is either 3/14 or 1/8
P(blue) = 3/8 +1/8 =19/56 = 0.339
It can hold 12l more of water.
Let the number be x.
<span>0.75 % * x = 10 </span>
<span>0.75/100 * x = 10 </span>
<span>0.0075 * x = 10 </span>
<span>x = 10/0.0075 = 1333.33</span>
There are 10 guppies, so we do 25-10
Which equals to 15
Answer is 3/5