Any number ends with 0, 1, 2, 3, 4, 5, 6, 7, 8 or 9
Given any number. The square of this number is the last digit of square of the original numbers units digit.
For example
23*23 ends with 9 (3*3=9)
149*149 ends with 1 (9*9=81)
2564*2564 ends with 6 (4*4=16)
and so on
so all the possible unit digits of a square number are {0, 1, 4, 5, 6, 9}
because:
0*0= 0 ; 1*1=1; 2*2=4; 3*3=9; 4*4=16; 5*5=25, 6*6=36; 7*7=49; 8*8=64, 9*9=81
Thus, the probability that the square of a number selected from any set of numbers being 7, is 0.
Answer: 0
