The distribution of a random variable X is given below:

Question

X-x	-2	-1	0	1	2	3
P(X-x)	$\large\frac{1}{10}$	K	$\large\frac{1}{5}$	2k	$\large\frac{3}{10}$	k

The value of k is:

$(1)\;\large\frac{1}{10}\\(2)\;\large\frac{2}{10} \\(3)\;\large\frac{3}{10}\\(4)\;\large\frac{7}{10}$