Maths Thinking.

For maths  i  worked with my maths group,and we were learning how to jump to the nearest ten by using  the jumping line.Our first number to start the question was 11 so we had to jump to   the nearest ten so the new number  would of been 20.Then from 20 i jumped to 50 so i jumped 30 to get to 50.Then from 50 i plused another 50 and then i used all my numbers to get to a hundred and then  my answer was  89.