Answer:
<em>The probability that she uses gray or yellow is 0.93</em>
Step-by-step explanation:
Suppose,
,
and
represent the events of using gray, blue and yellow colors respectively.
So,
and 
The probability that she uses gray and yellow is 0.62 , that means 
<u>The formula we will use here:</u> 
According to the above formula.....

So, the probability that she uses gray or yellow is 0.93