Jonathan is studying for his exams. He studies for 1 hour on the first day and then adds an extra hour each day. How many hours will Jonathan have studied by the end of the tenth day?
On the first day, Jonathan studied for 1 hour.
On the second day, he studied for 1 + 1 = <<1+1=2>>2 hours.
On the third day, he studied for 2 + 1 = <<2+1=3>>3 hours.
On the fourth day, he studied for 3 + 1 = <<3+1=4>>4 hours.
On the fifth day, he studied for 4 + 1 = <<4+1=5>>5 hours.
On the sixth day, he studied for 5 + 1 = <<5+1=6>>6 hours.
On the seventh day, he studied for 6 + 1 = <<6+1=7>>7 hours.
On the eighth day, he studied for 7 + 1 = <<7+1=8>>8 hours.
On the ninth day, he studied for 8 + 1 = <<8+1=9>>9 hours.
On the tenth day, he studied for 9 + 1 = <<9+1=10>>10 hours.
In total, by the end of the tenth day, Jonathan would have studied for 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 = <<1+2+3+4+5+6+7+8+9+10=55>>55 hours. Answer: \boxed{55}.