What even number can be divided by 7 and 3 without a remainder?

Answer 1

7 times 3=21, so 21 is part of the answer somehow. However, 21 is an odd number.

Now, if we multiply 21 X 2= 42 The answer is an even number.

42/3=14 has no remainder

42/7=6, again no remainder

So 42, and any whole multipleof 42, would be a satisfactory answer.