In the book One Grain of Rice, a girl receives a reward that starts with one grain of rice on day one, two grains on day two, four on day three and eight on day four. Each day, she receives double the number of grains of rice. How many grains of rice does she receive on the 20th day?
A)400
B)1,048,576
C)2,782,184
D)40

Question

Quizplus · Accepted Answer

To find the amount of rice on the 20th day, we need to keep doubling the amount from the previous day. So, on the 20th day, she would have received 2^19 grains of rice (since we started with one grain on day one). 2^19 is equal to 1,048,576, so the answer is B.

In the Book One Grain of Rice, a Girl Receives