In the set of consecutive integers from 21 to 46 , inclusive, there are 2 integers that are multiples of both 2 and 7. How many integers in the set are mulitples of neither 2 nor 7 ?.

The answer is 11 but
Please show me how to do it

x/3-10=8

x/3=18

x=48

answer is because 4×10=40

and 98×4= is 392

40,392

the functions have the same rate of change i think. i narrowed it down to this answer and "the rate of change of tour 1 is greater" but i got it wrong using that answer so im assuming its the answer above. (this is a question i also answered from the iready site if anyone needs a reference)

the answer is 40.

proof: