explain how you could add 678 + 303 using mental math
okay well I do it like this. 3+8=11. I put a 1 down and carry the other. so I do 7+0+1=8 so now I have 81, and last I do 6+3=9. so the answer would be 981.
Have a nice day!
add the hundreds first then the tenths then the units. so add 600 +300 which is 900 then 70 +0 which is 70 then 8+3 which is 11 then add them all up which is 981.