If the weekly income (in $Rs$ ) of $10$ persons are as follows, then
$(1)$ What percentage of persons whose weekly income are included in the range $\bar{x} \pm s ?$
$(2)$ What percentage of persons whose weekly income are included in the range $\bar{x} \pm 2 s$ ?
$350,327,320,385,360,340,380,345,400,372$
→Verify whether relations between the elements of the sets given below are
functions or not.
(1) $\mathrm{A}=\{1,2,3,4\}, \mathrm{B}=\{3,5,7,9\}$, and relation is $f(x)=2 x+1, x \in \mathrm{A}$
(2) $\mathrm{P}=\left\{-\frac{1}{2}, 0,1\right\}, \mathrm{S}=\{10\}$, and rule is $k(x)=10, x \in \mathrm{P}$
(3) $\mathrm{A}=\{2,5,6\}, \mathrm{B}=\left\{1, \frac{3}{2}, \frac{9}{5}, \frac{11}{7}, \frac{13}{6}\right\}$, and rule is $y=\frac{2 x-1}{x+1}, x \in \mathrm{A}$
(4) $\mathrm{B}=\{-1,0,1,3\}, \mathrm{C}=\{-5,-3,-1,1,3\}$, and rule is $h(x)=2 x+3, x \in \mathrm{B}$
→The data on quantity of wheat sold (in $\ kg$ ) in a grocery shop during $30$ days are as follows.Prepare a frequency distribution such that class length is $50$ and one of the classes is $250-299$.
$150,290,245,260,100,180,275,390,320,75,140$, $249,195,255,340,190,300,90,295,230,135,250$,$375,165,280,130,330,270,200,240 .$
Answer the following questions on the basis of frequency distribution:
$(1)$ Find the least possible sale of wheat of $20 \%$ days with more sale.
$(2)$ What is the expected sale of $5$ days in the fourth class?
$(3)$ Obtain the boundary points of fifth class.
$(4)$ Find the most possible sale of wheat of $20 \%$ days with less sale.
$(5)$ State the lower limit and upper limit of third class.
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