we can find the missing number by firstly finding the sum of digits of the given numbers and then subtract it from those multiple of 3, which are greater than this sum to get the smallest and greatest digits.
i) 6+7+2+4=19
multiples of 3 greater than 19 are 21,22,27,30
therefore, 21-19=2, 24-19=5, 27-19=8, 30-19=11
smallest digit=2 greatest digit=8
ii) 4+7+6+5+2=24
24 is a multiple of 3 so smallest digit is 0 greater than 24 are 27,30,33,36
It has to be go in the opposite direction and x=4 so the answer will have to be y=something and if the line has the point (5,7) then the line must be y=7