The Devil's Arithmetic is about a girl, Hannah Stern, who is tired of remembering about the Holocaust and Passover. When her family goes to Grandma Belle and Grandpa Will's house for Passover, she wishes she were somewhere else. When she is asked to open the door for Elijah, she is transported back to World War II. She is called Chaya by her Aunt Gitl and Uncle Shmuel. Shmuel is going to be married the next day to Fayge, the rabbi's daughter, and Chaya is going, too. Gitl, Shmuel, and Chaya travel down the road to the wedding with all the wedding gifts and guests. When they reach the shul for the wedding, big black trucks block the way. At this point, Chaya realizes what year it is, and to whom those trucks belong.
Chaya tries to warn her friends and family about the Nazis, but they think she is crazy, and they don't believe her. The men tell the Jews that they are being resettled and that all the other guests have been resettled already. All the guests and family are forced into the trucks and locked in for two days. When they get out of the trucks, they are loaded onto two boxcars on a train for a few days. During the time in the boxcars, a child and an infant die. When the boxcars finally stop and the people are forced out, they see a camp and they know they are not being resettled. Chaya, Gitl, Shmuel, and Fayge and all the rest are sent in the showers, get their heads shaved, and receive a tattoo telling what they are, and what number they are. The men and women are separated into different barracks, and each person is given a hard wooden bed.
Chapter: 15- 19
Chaya, Gitl, and all the other zugangi (newcomers) are given a meal of hard bread and potato soup.
The bowl they are given became theirs. If they lose it, they will not receive another one. Rivka hands out the bowls. She catches Chaya and tells her how to survive. "It is a brutal arithmetic. But I - I am alive. You are alive. As long as we breathe, we can see and hear. As long as we can remember, all those gone before are alive inside us."
Gitl also explains The Devil's Arithmetic - "each day she remained alive, she remained alive. One plus one plus one."
Chaya learns how to survive although some of her friends become musselman, and they do not care if they live or go into "Lilith's Cave." Near the end of the book, a guard finds Chaya, Rivka, and a few other girls talking and not working.