What is mental math for 6x298

Lay it out in your head as:

298

x 6

Think what is 8 times 6? (48)

9 times 6? (54) then add on the 4 carried over (58)

2 times 6? (12) then add on the 5 carried over (17)

And your answer is 1,788.

Take 298 and multiply it by 3. You will get 894. Take the other 298 and multiply that by 3. You will also get 894. Add 894+894 and you will get 1788.