Congruences
Prepared by:
Joseph Malkevitch
Department of Mathematics and Computing
York College (CUNY)
Jamaica, New York 11451-0001
email: joeyc@cunyvm.cuny.edu
web page: www.york.cuny.edu/~malk
1. Find the value of the ? for the congruences below:
a. 17 ? mod 10
b. 33 ? mod 10
c. 10023223 ? mod 10
d. -12 ? mod 10
e. -69 ? mod 10
2. For each of the congruences below state if it is correct or not:
a. - 15 3 mod 6
b. 45 26 mod 9
c. 39 -1 mod 4
d. -11 -3 mod 4
e. (-3)4 -1 mod 20
f. -42 -2 mod 7
g. 33 2 mod 5