CAT 2004 — QA Question 28
Number TheoryEasy
Passage / Data
Answer the following question based on the information given below.
In an examination, there are 100 questions divided into three groups A, B and C such that each group contains at least one question. Each question in group A carries 1 mark, each question in group B carries 2 marks and each question in group C carries 3 marks. It is known that the questions in group A together carry at least 60% of the total marks.
The remainder, when (1523 + 2323) is divided by 19, is:
Answer & solution
- A
4
- B
15
0
- D
18
Solution
(an + bn) is always divisible by (a + b) if n is odd
∴ (1523 + 2323) is divisible by (15 + 23) ie, 38.
⇒ 1523 + 2323 = 38x, which is divisible by 19.
⇒ Remainder when (1523 + 2323) is divided by 19 is 0.
Hence, option (c).