Elongation (in %) of steel plates treated with aluminium are random with probability density function
f(x)={x/250 20
a)What proportin of steel plates have elongations greater than 25 %?
b)Find the mean elongation.
c)Find the variance of the elongations.
d)Find the standard deviation of the elongations.
e)Find the cumulative distribution function of the elongations.
f)A particular plate elongates 28%. What proportion of plates elongate more than this?