u just make the number shorter e.g.
1.7 is rounded off to 2
Ten integers can be rounded off to 280. An infinite number of numbers can be rounded off to 280.
999 of them.
Since numbers equal to or greater than 5 are rounded up, and numbers equal to or less than 4 are rounded down, the largest 4-digit number that can be rounded off to 3000 would be 3004.
15 to 24
3 499
25549
45 to 54
Infinitely many.
35 to 44
245 to 254
The numbers from 75 to 84 are rounded off to 80 to the nearest ten
There are infinite amount of numbers that can be rounded to one:0.990.9990.99990.9980.9970.9961.011.051.4999999999, etc.