In one group, 300 people out of 450 workers were female. Then 50 male workers joined the group. An employee is randomly selected from the group. Find the probability of choosing a male worker.

(A)   \(\dfrac {2} {5}\)

(B)   \(\dfrac {3} {5}\)

(C)   \(\dfrac {3} {10}\)

(D)   \(\dfrac {7} {10}\)

Table below is shows a survey on how students come to school everyday.

\(\begin {array}{|l|c|} \hline \text {Type of vehicle}& \text {Number of students} \\\hline \text {Bus}& \text {120} \\\hline \text {On foot}& \text {105} \\\hline \text {Car}& \text {45} \\\hline \text {Motorcycle}& \text {130} \\\hline \end {array} \)

Find the probability of students come to school by car or motorcycle.

(A)   \(\dfrac {7}{16} \)

(B)   \(\dfrac {9}{16} \)

(C)   \(\dfrac {13}{40} \)

(D)   \(\dfrac {9}{80} \)

It is given that the universal set

\(\{\xi = {x:1 \le x \le 12, x \text{ is an integer}}\}\).

A number is chosen at random from the universal set.

Find the probability that the number chosen is a multiple of 4.

(A)  \(\dfrac {1}{12}\)

(B)  \(\dfrac {1}{3}\)

(C)  \(\dfrac {1}{4}\)

(D)  \(\dfrac {3}{4}\)