Question

109. For how many non-negative integer values of 'x' is
|||||||x - 1| - 2| - 3| - 4| -5| -6| -7| < 9
(a) 35
(b) 36
(c) 37
(d) 38


NOTE* These are modulus..so please dont consider it as 1....​

Answer 1

We must have x1 ≤ 20 or x1 ≥ 21. We have just shown how to calculate this

second value (with ≥ requirements), so we count by complement. Our result is

44

4

−

20 + 5 − 1

5 − 1

=

44

4

−

24