55.7 to the nearest ten is 56 while 265.4 round to the nearest ten is 265.
Since numbers from 0 - 4 turn into a zero and the numbers 5-9 turn into a zero (meaning it cancels) and carry a point to the next number. So for example, the number 38.7 rounded to the nearest ten is 39. Since from the right side, the 7 is higher then 5 that means it cancels and a point goes to the eight turning it into a 9. So 38.7 rounded to the nearest ten is 39.