NTSE MATHS#2
Number Theory
Level
3
When a natural number x is divided by 5, the remainder is 2. When a natural number y is divided by 5, the remainder is 4. The remainder is z when x+y is divided by 5. The value of (2z-5)/3 is
1
-2
-1
2
This section requires Javascript.
You are seeing this because something didn't load right. We suggest you, (a) try
refreshing the page, (b) enabling javascript if it is disabled on your browser and,
finally, (c)
loading the
non-javascript version of this page
. We're sorry about the hassle.
Let x = 5a + 2 , where a is a whole number
Therefore, x + y = 5(a+b) + 6 = 5(a+b+1) +1
( x + y )/5 gives remainder 1. So, z = 1.
Therefore, ( 2z - 5 ) /3 = (2-5)/3 =-1