First of all, use the given table to determine the total of the sample:
In-like skates Roller skates
Age 8 6 2 8
Age 10 3 3 6
total 9 5 14
The required probability is given by the quotient in between the number of skater with roller skates and with age 10, over the total number of the sample, which is 14. There are 3 skaters with roller skates and age 10. Then, you have:
3/14
Hence, the probability is 3/14
