P(a or b)= p(a)+p(b)-p(a and b)
0.7=0.6+p(b)-0.3
p(b)=0.4
p(a or b)= p(a)+p(b)-p(a and b)
=0.6+0.4-0.3
=0.7
ANSWER 155 cats
Step by step explanation
No. of dogs = 50=d
No. of cats = 3.5x50- 20
=175-20
=155 cats
<span>E = {x|x is a perfect square between 1 and 9} = {1,4
</span><span>F = {x|x is an even number greater than or equal to 2 and less than 9}
</span><span>D = {x|x is a whole number}
</span>
answer
D ∩ (E ∩ F) = 4
