A set X consists of twenty distinct exponents of 3. Suppose Y consists of all positive integers each of which can be expressed as a difference of two integers belonging to X. Then what is the number of integers Y contains?
A. 190
B. 210
C. 380
D. 400
Answer:A
A set X consists of twenty distinct exponents of 3. Suppose Y consists of all positive integers each of which can be expressed as a difference of two integers belonging to X. Then what is the number of integers Y contains?
A. 190 B. 210 C. 380 D. 400