Natasha had some T-shirts that she wanted to donate. 3 of them were torn and she had to throw them away. She then packed them equally into boxes. Each box could either contain 6 or 7 T-shirts. What is the smallest possible number of T-shirts Natasha had at first?
Level 3
Two lighthouses flash their lights every 36 seconds and 30 seconds. If they flash together at 8:10 p.m., at what time would the two lighthouses flash their lights together again?
Level 3
Paul has a bell that rings every 4 minutes. Lucy has a bell that rings every 7 minutes. The 2 bells ring together at 11 a.m. What time will the 2 bells ring together again?