How to find Quartiles

1, 3, 3, 4, 5, 6, 6, 7, 8, 8
how we will divide this data into quartiles??

As explained in the video Q1, Q2, Q3 are 25th, 50th, 75th percentile of the data.
Refer to Shikhar Dhawan’s T20 Scores example from the video for explaination.

Q1 will be 3
Q2 will be 5.5
Q3 will be 7.25

see in the example there are 10 elements in the data .so how these elements will be divided in 4 equal parts.
in the video lecture there were 20 elements and each quartiles were having 5 elements in each box i.e first 25% data ,then second 25% data and so on.

You’re right, in such case you can use the percentile formula to calculate quartiles.