How do you get 12 times 7 by multiplying 6 times 7?

Answer 1

Just as 12 is twice as much as 6, so too is 12 sets of something twice as many as 6 sets of the same thing. It matters not what that thing is.

Think of a week as an example. It has seven days in it. 12 weeks is 12 sets of 7 days. 6 weeks is 6 sets of 7 days. 12 weeks is twice 6 weeks.

So, if we calculate that 6 * 7 = 42 then we can calculate that 12 * 7 = 42 * 2 = 84.