Answer: 1234567890987654321+0987654321234567890= 2.2222222e+18
Step-by-step explanation: So, you add 1234567890987654321 and 0987654321234567890 and you will get 2.2222222e+18 and then if you don't get that in your head try using a calculator to help you figure the equation you are doing out so you don't get stuck on it for hours at a time wasting your teacher's time because you can hurt the teacher's feelings if you don't do it at all because some of the teacher's love teaching and will help you if you need any help so ask for help if you need it.