Question 1083281
Define
A = probability that X is equal to 0 = 0.55
B = probability that X is equal to 1 = 0.15
C = probability that X is equal to 2 = 0.10
D = probability that X is equal to 3 = 0.10
E = probability that X is equal to 4 = 0.04
F = probability that X is equal to 5 = 0.03
G = probability that X is equal to 6 = 0.03


Using the probabilities defined above, we can say
{{{P(X <= 2) = A+B+C}}}
{{{P(X <= 2) = 0.55+0.15+0.10}}}
{{{P(X <= 2) = 0.80}}}


<font color=red>The final answer is 0.80</font>


Note: if you wish, you can also write it like this
{{{P(X <= 2) = P(X = 0)+P(X = 1)+P(X = 2)=0.55+0.15+0.10=0.80}}}
but in my opinion it's a bit clunky due to all the equal signs. The letter notation might be easier to read.