How to calculate the Q1 if the problem is like this : C

How to calculate the Q1 if the problem is like this :
Calculate the quartile deviation of the following frequency distribution for the number of valentine cards by certain bookstore within 60 days before feb. 14
# of cards
10-18 1
19-27 3
29-36 4
37-45 7
46-54 12
55-63 13
64-72 13
73-81 7
82-90 3
91-99 1
N= 64
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