Robert likes to eat tacos at Chipotle
How many unique letters are there in the sentence?
r
o
b
e
t
l
i
k
s
a
c
h
p
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There are 13 unique letters.
Of them,
Consonants = 9
Vowels = 4
Selecting a consonant is 9 out of 13 chances, hence, the probability is: