Number of tiguers: x + 2
Number of Lions: x
Number of bears:(x+2)+1=(x+3)
We can suggest this equation:
(x+2) + (x)+(x+3)=20
3x+5=20
3x=20-5
3x=15
x=15/3
x=5.
Therefore:
Number of tiguers: x + 2=5+2=7
Number of Lions: x=5
Number of bears:(x+2)+1=(x+3)=5+3=8.
Answer: there are 7 tiguers, 5 lions and 8 bears.