165 Ting Ting's beads* (4 Sherrie's beads/ 5 Ting Ting's beads)= 132 Sherrie's beads.
132 Sherrie's beads* (1 Roxanne's bead/ 2 Sherrie's beads)= 66 Roxanne's beads.
Now that we know the number of beads Roxanne and Ting Ting have, let's subtract:
165 beads- 66 beads= 99 beads.
Hope this would help :))