1. If the integer k has remainder 5 when divided by 6, what is the remaider when 2k is divided by 6?
a) 0 b) 1 c) 2 d) 3 e) 4
Answer is 4. How to count?
2. The greatest prime factor of 3^5
or
The greatest prime factor of 5^3
Answer is B. (my answer was A)
3. Of the following which is most nearly equal to 2/3?
a) 3/4 b) 5/6 c) 7/9 d) 11/15 e) 15/21
Answer is 15/21. How it is possible to count without a lot of calculations?
4. and 5. Problems are attached.