A coffee shop sold 9 cups, 3 pints, and 7 quarts of coffee. Express the number of cups of coffee in base two.

Number of cups of coffee = 9

Expressing to base 2

Bases of 2: 1, 2, 4, 8, 16, ...

Number lower than 9 and a base of 2 is 8.

8 goes into 9 once: 1 that is (9 - (1) 8=1)

Next is 4. 4 goes into the balance 0 times: 10 that is (1 - (0) 4=1)

Next is 2. 2 goes into balance 0 times: 100 that is (1 - (0) 2=1)

Final number is 1. 1 goes into balance once: 1001 that is (1 - (1) 1=0)

Therefore, 9 into base of 2 = 1001