Binomial distribution online calculator
You can see a sample solution below. Enter your data to get the solution for your question
$$ \displaylines{---} $$
$$ \displaylines{n(number\;of\;trials\;)=\;6
\\\;\\\;p\;(probability\;of\;success\;\;)=\;0.5
\\\;\\\;q\;=\;p-1\;=\;0.5
\\ \\ P(less\;than\;or\;equal\;to\;3)=
\\ \\ P(x<=3)
\\ \\Formula\,for\,binomial\,distribution=
\, _{x}^{n}\textrm{C}(p)^{x}(q)^{n-x}
\\ \\ P(x<=3) = \:_{0}^{6}\textrm{C}(0.5)^{0}(0.5)^{6}
+
_{1}^{6}\textrm{C}(0.5)^{1}(0.5)^{5}
+
_{2}^{6}\textrm{C}(0.5)^{2}(0.5)^{4}
+
_{3}^{6}\textrm{C}(0.5)^{3}(0.5)^{3}
\\ \\ =
0.01562500
+
0.09375000
+
0.23437500
+
0.31250000
\\ \\ =
\mathbf{\color{Red}{0.65625}}
} $$