2x+12 would be the answer
223
-119
104
In stead of doing 3-9 and 2-1 do 23-19 then 2-1
500,000
The nearest hundred thousand would be 500,000 and 600,000, but since 541,776 has 4 in next unit, it rounds down.
The least common multiple (LCM) of a set of numbers is the lowest value that all of the numbers can be divided by and have a result of a whole number.
In this case, the least common multiple is 21 because 21/7=3 and 21/21=1.