Level 1
A mailman delivered a total of 1889 letters over a period of 2 days. He delivered 454 letters on the first day and the rest on the second day. How many letters did the mailman deliver on the second day?
Level 3
Dennis saved some money on the first week. Each following week, he managed to save $8 more than the week before. He saved a total of $100 after 4 weeks. How much money did he save on the 3rd week?