CAT 2020 Slot 3 — QA Question 15
Number TheoryEasy
Let N, x and y be positive integers such that N = x + y, 2 < x < 10 and 14 < y < 23. If N > 25, then how many distinct values are possible for N?
Answer & solution
Answer: 6
Solution
Easy
List the integer ranges of and to get the maximum possible . Since can take every integer up to that maximum, just count the integers exceeding .
1
Integer ranges. From $2
2
Maximum of .
Every integer from the minimum up to is attainable, so once the possible values are the integers to .
3
Count the values with .