Ramesh chooses a date at random in January for a party (see the following figure).

Find the probability that he chooses :

(i) a Wednesday

(ii) a Friday

(iii) a Tuesday or a Saturday.

JANUARY

Mon.		6	13	20	27
Tue.		7	14	21	28
Wed.	1	8	15	22	29
Thu.	2	9	16	23	30
Fri.	3	10	17	24	31
Sat.	4	11	18	25
Sun.	5	12	19	26

Since, there are 31 days in January.

∴ No. of possible outcomes = 31.

(i) There is wednesday on 1st, 8th, 15th, 22nd and 29th of January.

∴ No. of favourable outcomes = 5

P(getting a Wednesday) = $\dfrac{\text{No. of favourable outcomes}}{\text{No. of possible outcomes}} = \dfrac{5}{31}$.

Hence, the probability of getting a Wednesday = $\dfrac{5}{31}$.

(ii) There is friday on 3rd, 10th, 17th, 24th and 31st of January.

∴ No. of favourable outcomes = 5

P(getting a Friday) = $\dfrac{\text{No. of favourable outcomes}}{\text{No. of possible outcomes}} = \dfrac{5}{31}$.

Hence, the probability of getting a Friday = $\dfrac{5}{31}$.

(iii) There is tuesday on 7th, 14th, 21st and 28th of January and Saturday on 4th, 11th, 18th and 25th of January.

∴ No. of favourable outcomes = 8.

P(getting a Tuesday or Saturday) = $\dfrac{\text{No. of favourable outcomes}}{\text{No. of possible outcomes}} = \dfrac{8}{31}$.

Hence, the probability of getting a Tuesday or Saturday = $\dfrac{8}{31}$.