If x, y are positive integers, what is the remainder when 2^(4x +2)+y is divided by 5?
1) x=3
2) y=1
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If x, y are positive integers, what is the remainder when 2
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The remainder question that is divided by 5 will have a cycle of 4. In other words, (~2)^1=~2, (~2)^2=~4, (~2)^3=~8, (~2)^4=~6. Hence, it has a cycle of
4-> 2->4->8->6->2->4->8->6.
If we modify the original condition and the question, when we divide 2^4x+2+y by 5, we do not have to know 4x in 4x+2. Hence, from 2^2+y, we only have to know y. The correct answer choice is, thus, B.
- Forget conventional ways of solving math questions. In DS, Variable approach is the easiest and quickest way to find the answer without actually solving the problem. Remember equal number of variables and independent equations ensures a solution.
4-> 2->4->8->6->2->4->8->6.
If we modify the original condition and the question, when we divide 2^4x+2+y by 5, we do not have to know 4x in 4x+2. Hence, from 2^2+y, we only have to know y. The correct answer choice is, thus, B.
- Forget conventional ways of solving math questions. In DS, Variable approach is the easiest and quickest way to find the answer without actually solving the problem. Remember equal number of variables and independent equations ensures a solution.
Math Revolution
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Score an excellent Q49-51 just like 70% of our students.
[Free] Full on-demand course (7 days) - 100 hours of video lessons, 490 lesson topics, and 2,000 questions.
[Course] Starting $79 for on-demand and $60 for tutoring per hour and $390 only for Live Online.
Email to : [email protected]