Answer:
100000000000000000000000000000000000000000000000000000000000000000000000000000
0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
5050-3030=she needs 2020 markers.
2020/1010=2, so she needs to buy 2 more packs