JEE Main 201911 Jan, Evening shiftMathematicsMediumSets, Relations and Functions168× since 2002
The number of functions f from {1, 2, 3, ...., 20} onto {1, 2, 3, ...., 20} such that f(k) is a multiple of 3,
whenever k is a multiple of 4, is :
JEE Main 2019 · 11 Jan, Evening shift · Q3798