We know that,

Probability of occurrence of an event

Total possible outcomes are alphabets from a to z

Desired outcomes are a, e, i, o, u

Total no.of outcomes are 26 and desired outputs are 5

Therefore, the probability of picking a vowel

Conclusion: Probability of choosing a vowel is

(ii) We know that,

Probability of occurrence of an event

Total possible outcomes are all alphabets from a to z

Desired outcomes are all alphabets except a, e, i, o, u

Total no.of outcomes are 26 and desired outputs are 21

Therefore, the probability of picking a consonant

Conclusion: Probability of choosing a consonant is