Answer:
It's 90 because we'll make it equal
I believe this is the way to solve it.
22 - 2 = 20
20 is 90.9% of 22
So the probability of choosing a student with a sibling at random should be 90.9% (or you can round up to 91%)
I hope this helps :)
There are 80 children. 45 of them are girls. The amount of boys is equal to:

That means there are 45 girls and 35 boys.
The ratio of boys to girls is: 
Simplify:

Your answer is 7:9
Idk sorry :( i dont have enuff time to anwser..but remember: do the equation backwards..